x86/efi: fix a -Wtype-limits compilation warning

mainline inclusion
from mainline-v5.2-rc7
commit 919aef44
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I67RIP
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=919aef44d73d5d0c04213cb1bc31149cc074e65e



--------------------------------

Compiling a kernel with W=1 generates this warning,

arch/x86/platform/efi/quirks.c:731:16: warning: comparison of unsigned
expression >= 0 is always true [-Wtype-limits]

Fixes: 3425d934 ("efi/x86: Handle page faults occurring while running ...")
Signed-off-by: Qian Cai <cai@lca.pw>
Acked-by: "Prakhya, Sai Praneeth" <sai.praneeth.prakhya@intel.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Ding Hui <dinghui@sangfor.com.cn>