envsetup: drop unnecesary exports

export -f is a bashism and we don't actually need it, so lets remove it.

Change-Id: I9228cef0c4a9543b3d34fdc39a368ad0238431e2
envsetup: Mark zsh as compatible

Basic functionality has been tested on zsh 5.0.2 and has been found to
work correctly.

Change-Id: I02e5e3bedf56b43104c280d9737ae7b334357643
Support building with GNU make 4.0

* It works just fine, no need for the warning.

Change-Id: Ifa2ab17454edfcd8b7840a7534f70576286f2864
Merge remote-tracking branch 'cm/cm-11.0' into cm-11.0

Conflicts:
	envsetup.sh