Remove gperf usage from toolchain

It turns out that gperf-3.1 changed types in the generated code in ways
that aren't even trivially detectable without having to generate a test-file.

It's just not worth using tools and libraries from clowns that don't
understand or care about compatibility.  So get rid of gperf.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Documentation/dontdiff

@@ -259,5 +259,4 @@ wakeup.bin
 wakeup.elf
 wakeup.lds
 zImage*
-zconf.hash.c
 zoffset.h