powerpc: Fix compiler warning in arch/powerpc/mm/mem.c
powerpc: Fix compiler warning in arch/powerpc/mm/mem.c

Explicitly cast to unsigned long long, rather than u64.

Signed-off-by: Tony Breeds <1001e8702733cced254345e193c88aaa47a4f5de@bakeyournoodle.com>
Signed-off-by: Paul Mackerras <19a0ba370c443ba08d20b5061586430ab449ee8c@samba.org>

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