proc/vmcore: fix vmcore_alloc_buf() kernel-doc comment

proc/vmcore: fix vmcore_alloc_buf() kernel-doc comment

Fix a spelling problem to remove warnings found by running
scripts/kernel-doc, which is caused by using 'make W=1'.

fs/proc/vmcore.c:492: warning: Function parameter or member 'size' not
described in 'vmcore_alloc_buf'
fs/proc/vmcore.c:492: warning: Excess function parameter 'sizez'
description in 'vmcore_alloc_buf'

Link: https://lkml.kernel.org/r/20220129011449.105278-1-yang.lee@linux.alibaba.com
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Acked-by: Baoquan He <bhe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>