busybox: Fix depmod patch

busybox: Fix depmod patch

The original patch was actually allowing .debug modules
though which was in-correct. This change blocks the
parsing of .debug modules (which is correct). As noted in
[YOCTO #15022] this should address the empty modules.dep
when using the BusyBox depmod.

Signed-off-by: Saul Wold <saul.wold@windriver.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
(cherry picked from commit 339c3c3abe8d405cfe7b3f34db9b3547bcaaf878)
Signed-off-by: Steve Sakoman <steve@sakoman.com>