lib/vdso: use "grep -E" instead of "egrep"

stable inclusion
from stable-v5.10.157
commit d21d26e65b5f6d14c453f924d1edd689ad7b855e
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I7MU59

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=d21d26e65b5f6d14c453f924d1edd689ad7b855e

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

commit 8ac3b5cd upstream.

The latest version of grep claims the egrep is now obsolete so the build
now contains warnings that look like:
	egrep: warning: egrep is obsolescent; using grep -E
fix this up by moving the vdso Makefile to use "grep -E" instead.

Cc: Andy Lutomirski <luto@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: NVincenzo Frascino <vincenzo.frascino@arm.com>
Link: https://lore.kernel.org/r/20220920170633.3133829-1-gregkh@linuxfoundation.orgSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Nsanglipeng <sanglipeng1@jd.com>

lib/vdso/Makefile

@@ -17,6 +17,6 @@ $(error ARCH_REL_TYPE_ABS is not set)
 endif
 
 quiet_cmd_vdso_check = VDSOCHK $@
-      cmd_vdso_check = if $(OBJDUMP) -R $@ | egrep -h "$(ARCH_REL_TYPE_ABS)"; \
+      cmd_vdso_check = if $(OBJDUMP) -R $@ | grep -E -h "$(ARCH_REL_TYPE_ABS)"; \
 		       then (echo >&2 "$@: dynamic relocations are not supported"; \
 			     rm -f $@; /bin/false); fi