Include machine/acle-compat.h in cdefs.h on arm if the compiler doesn't

Include machine/acle-compat.h in cdefs.h on arm if the compiler doesn't
have ACLE support built in.  The ACLE (ARM C Language Extensions) defines
a set of standardized symbols which indicate the architecture version and
features available.  ACLE support is built in to modern compilers (both
clang and gcc), but absent from gcc prior to 4.4.

ARM (the company) provides the acle-compat.h header file to define the
right symbols for older versions of gcc.  Basically, acle-compat.h does
for arm about the same thing cdefs.h does for freebsd: defines
standardized macros that work no matter which compiler you use.  If ARM
hadn't provided this file we would have ended up with a big #ifdef __arm__
section in cdefs.h with our own compatibility shims.

Remove #include <machine/acle-compat.h> from the zillion other places (an
ever-growing list) that it appears.  Since style(9) requires sys/types.h
or sys/param.h early in the include list, and both of those lead to
including cdefs.h, only a couple special cases still need to include
acle-compat.h directly.

Loves it:     imp