Fix RPATH issues for qt/plugin binaries (#2018)

- Add special handling for shared objects copied from qt/plugins to correct the RPATH to reflect destination folder

Signed-off-by: spham-amzn <spham@amazon.com>

cmake/Platform/Linux/RuntimeDependencies_linux.cmake

@@ -5,5 +5,5 @@
 #
 #
 
-set(LY_RUNTIME_DEPENDENCIES_TEMPLATE ${LY_ROOT_FOLDER}/cmake/Platform/Common/runtime_dependencies_common.cmake.in)
+set(LY_RUNTIME_DEPENDENCIES_TEMPLATE ${LY_ROOT_FOLDER}/cmake/Platform/Linux/runtime_dependencies_linux.cmake.in)
 include(cmake/Platform/Common/RuntimeDependencies_common.cmake)

cmake/Platform/Linux/runtime_dependencies_linux.cmake.in

@@ -0,0 +1,30 @@
+#
+# Copyright (c) Contributors to the Open 3D Engine Project. For complete copyright and license terms please see the LICENSE at the root of this distribution.
+# 
+# SPDX-License-Identifier: Apache-2.0 OR MIT
+#
+#
+
+cmake_policy(SET CMP0012 NEW) # new policy for the if that evaluates a boolean out of "if(NOT ${same_location})"
+
+function(ly_copy source_file target_directory)
+    get_filename_component(target_filename "${source_file}" NAME)
+    get_filename_component(target_filename_ext "${source_file}" LAST_EXT)
+    cmake_path(COMPARE "${source_file}" EQUAL "${target_directory}/${target_filename}" same_location)
+    if(NOT ${same_location})
+        file(LOCK ${target_directory}/${target_filename}.lock GUARD FUNCTION TIMEOUT 300)
+        if("${source_file}" IS_NEWER_THAN "${target_directory}/${target_filename}")
+            file(COPY "${source_file}" DESTINATION "${target_directory}" FILE_PERMISSIONS @LY_COPY_PERMISSIONS@ FOLLOW_SYMLINK_CHAIN)
+            
+            # Special case, shared libraries that are copied from qt/plugins have their RPATH set to \$ORIGIN/../../lib 
+            # which is the correct relative path based on the source location. But when we copy it to their subfolder, 
+            # the rpath needs to be adjusted to the parent ($ORIGIN/..)
+            if("${source_file}" MATCHES "qt/plugins" AND "${target_filename_ext}" STREQUAL ".so")
+                file(RPATH_CHANGE FILE "${target_directory}/${target_filename}" OLD_RPATH "\$ORIGIN/../../lib" NEW_RPATH "\$ORIGIN/..")
+            endif()
+
+        endif()
+    endif()    
+endfunction()
+
+@LY_COPY_COMMANDS@