x86/mce: Restore MCE injector's module name

It was mce-inject.ko but it turned into inject.ko since the containing
source file got renamed. Restore it.

Fixes: 21afaf18 ("x86/mce: Streamline MCE subsystem's naming")
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-edac <linux-edac@vger.kernel.org>
Cc: Tony Luck <tony.luck@intel.com>
Link: https://lkml.kernel.org/r/20181218182546.GA21386@zn.tnic