BundleUtilities: Use more portable find ... -perm

Since find ... -perm +0111 is not clearly POSIX compliant and some Linux
versions refuse it, it is better to use longer but portable:

   find ... -perm \( -perm -0100 -o -perm -0010 -o -perm -0001 \)

Also quote last parameter of string(REPLACE ...) in case it is empty.
Merge topic 'fix-OSX-bundle-rpaths-and-Qt5' into next

27779efc BundleUtilities: Use more portable find ... -perm