chap-5.10.1 gcc unneeded reference to sysv4.h

[Gilles Espinasse]

gcc/config/rs6000/sysv4.h contain the define for the linker
GLIBC_DYNAMIC_LINKER "/lib/ld.so.1"
But gcc/config/i386/sysv4.h does not contain that define.

LFS does not support powerpc, so that's useless to adjust the linker in that
file.

Greg only add STANDARD_INCLUDE_DIR and STANDARD_STARTFILE_PREFIX_...
in one DL_HEADER file, so gcc/config/i386/sysv4.h need no changes.

I would suggest to refer to i386 directory directly and write
for file in $(find gcc/config/i386 -name linux64.h -o -name linux.h)

    Gilles