x86/speculation: Merge one test in spectre_v2_user_select_mitigation()

stable inclusion
from stable-v4.19.234
commit d86fc674172edc0794f84198405f59f00b71512a
category: bugfix
bugzilla: 186453, https://gitee.com/src-openeuler/kernel/issues/I50WBM


CVE: CVE-2022-0001

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

commit a5ce9f2b upstream.

Merge the test whether the CPU supports STIBP into the test which
determines whether STIBP is required. Thus try to simplify what is
already an insane logic.

Remove a superfluous newline in a comment, while at it.

Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Anthony Steinhauser <asteinhauser@google.com>
Link: https://lkml.kernel.org/r/20200615065806.GB14668@zn.tnic


[fllinden@amazon.com: fixed contextual conflict (comment) for 4.19]
Signed-off-by: Frank van der Linden <fllinden@amazon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Conflicts:
    arch/x85/kernel/cpu/bugs.c

Signed-off-by: Chen Jiahao <chenjiahao16@huawei.com>
Reviewed-by: Hanjun Guo <guohanjun@huawei.com>
Reviewed-by: Liao Chang <liaochang1@huawei.com>
Signed-off-by: Yongqiang Liu <liuyongqiang13@huawei.com>