livepatch/klp-build: add grep-override function

livepatch/klp-build: add grep-override function

Provide a custom grep() function to catch direct usage of the command.
Bare grep calls are generally incompatible with pipefail and
errexit behavior (where a failed match causes the script to exit).

Developers can still call grep via command grep if that behavior is
explicitly desired.

Acked-by: Song Liu <song@kernel.org>
Signed-off-by: Joe Lawrence <joe.lawrence@redhat.com>
Link: https://patch.msgid.link/20260310203751.1479229-6-joe.lawrence@redhat.com
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>