[PATCH] Add ABI mandated AT_ entries, prepare powerpc/dl-sysdep.c for new kernels

[Franz Sirl]

Hi,

this patch adds the PPC ABI mandated AT_[DIU]CACHEBSIZE and an additional 
AT_IGNOREPPC which will be used by newer kernels to compatibly move to the 
standard AUXV setup.
A patch actually setting cache variables and adjusting some mem* routines 
with it will follow later.
kernel-features.h needs a finalizing patch too as soon as the kernel patch 
reaches an official kernel.

Tested on both standard and fixed kernels.

Franz.

	* elf/elf.h (AT_DCACHEBSIZE, AT_ICACHEBSIZE, AT_UCACHEBSIZE,
	AT_IGNOREPPC): New defines.
	* sysdeps/generic/dl-sysdep.c (_dl_show_auxv): Print them.
	* sysdeps/unix/sysv/linux/kernel-features.h (__ASSUME_STD_AUXV):
	Define for newer powerpc kernels.
	* sysdeps/unix/sysv/linux/powerpc/dl-sysdep.c: Use the standard
	DL_FIND_ARG_COMPONENTS if __ASSUME_STD_AUXV is defined.