Skip a number of 'g++.dg/tree-prof/' test cases for '-fno-exceptions' testing

Running 'make check' with: 'RUNTESTFLAGS=--target_board=unix/-fno-exceptions',
'error: exception handling disabled' is triggered for C++ 'throw' etc. usage,
and per 'gcc/testsuite/lib/gcc-dg.exp:gcc-dg-prune':

    # If exceptions are disabled, mark tests expecting exceptions to be enabled
    # as unsupported.
    if { ![check_effective_target_exceptions_enabled] } {
        if [regexp "(^|\n)\[^\n\]*: error: exception handling disabled" $text] {
          return "::unsupported::exception handling disabled"
        }

..., which generally means:

    -PASS: [...] (test for excess errors)
    +UNSUPPORTED: [...]: exception handling disabled

However, this doesn't work for 'g++.dg/tree-prof/' test cases.  For example:

    [-PASS:-]{+UNSUPPORTED:+} g++.dg/tree-prof/indir-call-prof-2.C [-compilation,  -fprofile-generate -D_PROFILE_GENERATE-]{+compilation: exception handling disabled+}
    [-PASS:-]{+UNRESOLVED:+} g++.dg/tree-prof/indir-call-prof-2.C execution,    -fprofile-generate -D_PROFILE_GENERATE
    [-PASS:-]{+UNRESOLVED:+} g++.dg/tree-prof/indir-call-prof-2.C compilation,  -fprofile-use -D_PROFILE_USE
    [-PASS:-]{+UNRESOLVED:+} g++.dg/tree-prof/indir-call-prof-2.C execution,    -fprofile-use -D_PROFILE_USE

Dependent tests turn UNRESOLVED if the first "compilation" runs into the
expected 'UNSUPPORTED: [...] compile: exception handling disabled'.

Specify 'dg-require-effective-target exceptions_enabled' for those test cases.

	gcc/testsuite/
	* g++.dg/tree-prof/indir-call-prof-2.C: Specify
	'dg-require-effective-target exceptions_enabled'.
	* g++.dg/tree-prof/partition1.C: Likewise.
	* g++.dg/tree-prof/partition2.C: Likewise.
	* g++.dg/tree-prof/partition3.C: Likewise.
	* g++.dg/tree-prof/pr51719.C: Likewise.
	* g++.dg/tree-prof/pr57451.C: Likewise.
	* g++.dg/tree-prof/pr59255.C: Likewise.

gcc/testsuite/g++.dg/tree-prof/indir-call-prof-2.C

@@ -1,3 +1,4 @@
+/* Explicit { dg-require-effective-target exceptions_enabled } so that dependent tests don't turn UNRESOLVED for '-fno-exceptions'.  */
 /* { dg-options "-O" } */
 
 int foo1(void) { return 0; }

gcc/testsuite/g++.dg/tree-prof/partition1.C

@@ -1,3 +1,4 @@
+/* Explicit { dg-require-effective-target exceptions_enabled } so that dependent tests don't turn UNRESOLVED for '-fno-exceptions'.  */
 /* { dg-require-effective-target freorder } */
 /* { dg-options "-O2 -freorder-blocks-and-partition" } */
 

gcc/testsuite/g++.dg/tree-prof/partition2.C

@@ -1,4 +1,5 @@
 // PR middle-end/45458
+// Explicit { dg-require-effective-target exceptions_enabled } so that dependent tests don't turn UNRESOLVED for '-fno-exceptions'.
 // { dg-require-effective-target freorder }
 // { dg-options "-O2 -fnon-call-exceptions -freorder-blocks-and-partition" }
 

gcc/testsuite/g++.dg/tree-prof/partition3.C

@@ -1,4 +1,5 @@
 // PR middle-end/45566
+// Explicit { dg-require-effective-target exceptions_enabled } so that dependent tests don't turn UNRESOLVED for '-fno-exceptions'.
 // { dg-require-effective-target freorder }
 // { dg-options "-O2 -fnon-call-exceptions -freorder-blocks-and-partition" }
 

gcc/testsuite/g++.dg/tree-prof/pr51719.C

@@ -1,4 +1,5 @@
 // PR tree-optimization/51719
+// Explicit { dg-require-effective-target exceptions_enabled } so that dependent tests don't turn UNRESOLVED for '-fno-exceptions'.
 // { dg-options "-O -fpartial-inlining" }
 
 int

gcc/testsuite/g++.dg/tree-prof/pr57451.C

@@ -1,3 +1,4 @@
+// Explicit { dg-require-effective-target exceptions_enabled } so that dependent tests don't turn UNRESOLVED for '-fno-exceptions'.
 // { dg-require-effective-target freorder }
 // { dg-options "-O2 -freorder-blocks-and-partition -g" }
 

gcc/testsuite/g++.dg/tree-prof/pr59255.C

@@ -1,4 +1,5 @@
 // PR c++/59255
+// Explicit { dg-require-effective-target exceptions_enabled } so that dependent tests don't turn UNRESOLVED for '-fno-exceptions'.
 // { dg-options "-std=c++11 -O2" }
 
 struct S