the assumption stated in b67a0836

 is actually invalid - configure sets
build_all without debug_and_release there. debug_and_release does
actually imply build_all, though.

to make things less confusing, don't let configure inject
iphonesimulator_and_iphoneos into all projects, but handle it like
debug_and_release instead.

Change-Id: Ib7acdc63308a538862fc603428f81aba60bca08e
Reviewed-by: Jake Petroules <jake.petroules@qt.io>