[IA64] pgd_offset() constfication.
[IA64] pgd_offset() constfication.

when compile 2.6.25-rc8-mm1, below warning happend.
because walk_page_range pass argument as "const struct mm*",
but pgd_offset() receive as "struct mm*".

  CC      mm/pagewalk.o
mm/pagewalk.c: In function 'walk_page_range':
mm/pagewalk.c:111: warning: passing argument 1 of 'pgd_offset' discards qualifiers from pointer target type

Signed-off-by: KOSAKI Motohiro <70a1d3ef3e17a2bb0f09a1b2e6c86f607ed1d6d9@jp.fujitsu.com>
Signed-off-by: Tony Luck <e7984595ec0368ff920a7b3521dc7093683f6f26@intel.com>

KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs