Clean up duplicated code block

Two separate changes addressed the OUTPUT_TARGETS variable not being
set in the calling scope of _qt_internal_process_resource() for a
particular code path, but they did so at different places. Remove one
of them, since we don't need both.

Pick-to: 6.2
Change-Id: Ibc1052e886ec73a99231ada3b7a1bb9e7a873cc4
Reviewed-by: Alexey Edelev <alexey.edelev@qt.io>
Reviewed-by: Alexandru Croitor <alexandru.croitor@qt.io>
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>

src/corelib/Qt6CoreMacros.cmake

@@ -1848,9 +1848,6 @@ function(_qt_internal_process_resource target resourceName)
     if(isBinary)
         # Add generated .rcc target to 'all' set
         add_custom_target(binary_resource_${resourceName} ALL DEPENDS "${generatedOutfile}")
-        if(rcc_OUTPUT_TARGETS)
-            set(${rcc_OUTPUT_TARGETS} "" PARENT_SCOPE)
-        endif()
     else()
         # We can't rely on policy CMP0118 since user project controls it.
         # We also want SKIP_AUTOGEN known in the target's scope, where we can.