gcc-4.2.4: fix gcc build for sh4 and uclibc

gcc-4.2.4: fix gcc build for sh4 and uclibc
* add sh_unwind.patch which fixes gcc/config/sh/linux-unwind.h
  like mips or i386
* add cppdefaults_cross.patch which removes /usr/include path from
  gcc/cppdefault.c when, this is needed because sh4 uses fixheader
  and fixproto and then zeckes no-host-include code yelling
  at the /usr/include
* ATTENTION this may break sh4-native gcc, but I do not
  believe that someone would use gcc directly on sh4 arch,
  if there iare some crazy people doing it, I will fix it in
  another way
* do not bump PR because it only affects sh4 arch