prctl.h uses __BEGIN_DECLS but fails to include sys/cdefs.h
(where it's defined). Code which includes prctl.h without
previously including sys/cdefs.h will fail to compile.
Fixed.
Change-Id: If4c9f3308f08b93596dcd00e351ae786807e9320
This change fixes the prctl() declaration to match GLibc, and allow us
to build gcc-4.6 for Android (among other things). Note that this does
not change the source and binary interfaces.
Change-Id: I3900c957f0da8b3548cbe9da8c41d50099dc19d6
