generic: use __meminit annotation for crashlog_init_memblock

Fixes this section mismatch warning:
WARNING: vmlinux.o(.meminit.text+0xb14): Section mismatch in reference
from the function memblock_insert_region() to the function
.init.text:crashlog_init_memblock()
The function __meminit memblock_insert_region() references
a function __init crashlog_init_memblock().
If crashlog_init_memblock is only used by memblock_insert_region then
annotate crashlog_init_memblock with a matching annotation.

Also, remove the __init annotations from 'include/linux/crashlog.h'

SVN-Revision: 33137