Change file permission of checkvintf binary

Make checkvintf binary executable by setting file permission to
755

Test: development/vndk/tools/build_mixed -v 8.1.0
-m development/vndk/tools/modify_system_img.sh
system_dir device_dir out_dir system_dir/checkvintf
Bug: 74214049

Change-Id: Ic87a736b5a9e7c64fd69fac76404994fabff635f

vndk/tools/build_mixed

@@ -127,6 +127,7 @@ unzip "$DEVICE_TARGET_FILES_ARCHIVE" \
 ###
 # Check compatibility between the system and device.
 if [[ -f "$CHECK_TOOL" ]]; then
+    chmod 755 "$CHECK_TOOL"
     "$CHECK_TOOL" \
         "$DEVICE_ARTIFACTS_DIR"/META/vendor_manifest.xml \
         "$SYSTEM_ARTIFACTS_DIR"/META/system_matrix.xml