Fix snap build

snap/snapcraft.yaml

@@ -292,7 +292,7 @@ parts:
       - patches
 
   qt:
-    plugin: cmake
+    plugin: nil
     build-environment:
       - LDFLAGS: ${LDFLAGS:+$LDFLAGS} -s
     build-packages:
@@ -378,13 +378,6 @@ parts:
       - zlib1g
       - mesa-vulkan-drivers
       - xkb-data
-    cmake-generator: Ninja
-    cmake-parameters:
-      - -DCMAKE_BUILD_TYPE=Release
-      - -DCMAKE_INSTALL_PREFIX=/usr
-      - -DCMAKE_PREFIX_PATH=$CRAFT_STAGE/usr
-      - -DINSTALL_LIBDIR=/usr/lib/$CRAFT_ARCH_TRIPLET_BUILD_FOR
-      - -DINPUT_openssl=linked
     override-pull: |
       QT=6.8.0
 
@@ -396,6 +389,16 @@ parts:
       cd ../qtwayland
       find $CRAFT_STAGE/patches/qtwayland_${QT} -type f -print0 | sort -z | xargs -r0 git apply
       cd ..
+    override-build: |
+      cmake -GNinja -B $CRAFT_PART_BUILD \
+        -DCMAKE_BUILD_TYPE=Release \
+        -DCMAKE_INSTALL_PREFIX=/usr \
+        -DCMAKE_PREFIX_PATH=$CRAFT_STAGE/usr \
+        -DINSTALL_LIBDIR=/usr/lib/$CRAFT_ARCH_TRIPLET_BUILD_FOR \
+        -DINPUT_openssl=linked
+
+      cmake --build . -j$CRAFT_PARALLEL_BUILD_COUNT
+      DESTDIR="$CRAFT_PART_INSTALL" cmake --install .
     prime:
       - -./usr/bin
       - -./usr/doc