[CMake] Xcode and Cmake ReRun

[Johan Björk]

Hi guys,

I noticed that each XCode target has an associated CMake ReRun script
phase. Is there a specific reason for this (in difference to having
one target that all others depend on that does the ReRun check?)

It causes a fair few issues, it fails when you are parallelcompiling
targets (It'll start <number of cpus> copies of cmake at the same
time), secondly it adds quite some time to the build if you have many
targets
/Johan