Re: [OS-BUILD PATCH] redhat/Makefile: Fix RHJOBS grep warning

[Herton R. Krzesinski (via Email Bridge)]

From: Herton R. Krzesinski on gitlab.com
https://gitlab.com/cki-project/kernel-ark/-/merge_requests/2148#note_1174863...

So there is a problem in this expression I think, but it was already an
existing problem before this change.

If you have eg.: ```MAKEFLAGS="-j45"```, be at the beginning or -j being the
only option in the MAKEFLAGS, the expression will not match.

I think the expression need to be changed to: ```grep -Eo "(^|[ ])-j[0-9]*"```
So it matches either at the beginning, or as an option in the middle of other
options with the space.