kbuild: rpm-pkg: rename binkernel.spec to kernel.spec

Now kernel.spec and binkernel.spec have the exactly same contents.

Use kernel.spec for binrpm-pkg as well.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>

.gitignore

@@ -74,7 +74,7 @@ modules.order
 #
 # RPM spec file (make rpm-pkg)
 #
-/*.spec
+/kernel.spec
 /rpmbuild/
 
 #