Fix QMAKE_PRL_INSTALL_REPLACE for macOS

The regular expression with the alternative is not portable.
Use a separate QMAKE_PRL_INSTALL_REPLACE item.

This amends commit f00de33.

(cherry picked from commit 015d7f16cb)

Fixes: QTBUG-75950
Change-Id: I78e172053f8b05be7d595a1c9e1695ea658b0547
Reviewed-by: Iikka Eklund <iikka.eklund@qt.io>
Reviewed-by: Oliver Wolff <oliver.wolff@qt.io>

mkspecs/features/qt_common.prf

@@ -48,10 +48,14 @@ contains(TEMPLATE, .*lib) {
         lib_replace.match = $$rplbase/lib
         lib_replace.replace = $$qqt_libdir
     }
-    !equals(qt_libdir, $$rplbase/lib): \
-        lib_replace.match = \\($$lib_replace.match\\)\\|\\($$qt_libdir\\)
     lib_replace.CONFIG = path
     QMAKE_PRL_INSTALL_REPLACE += lib_replace
+    !equals(qt_libdir, $$rplbase/lib) {
+        qtlibdir_replace.match = $$qt_libdir
+        qtlibdir_replace.replace = $$qqt_libdir
+        qtlibdir_replace.CONFIG = path
+        QMAKE_PRL_INSTALL_REPLACE += qtlibdir_replace
+    }
 }
 
 # The remainder of this file must not apply to host tools/libraries,