linux-imx

kbuild: Do not run modules_install and install in paralel

Based on a x86-only patch by Andy Lutomirski <luto@amacapital.net>

With modular kernels, 'make install' is going to need the installed
modules at some point to generate the initramfs.

Signed-off-by: Michal Marek <mmarek@suse.cz>