intelmetool: free sb pci_dev struct allocated by pci_get_dev()

This fixes a memory leak in the activate_me() function.

Change-Id: I011b2f96122d8f88aed121352afe3f0d41edef60
Signed-off-by: Paul Wise <pabs3@bonedaddy.net>
Reviewed-on: https://review.coreboot.org/19561
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Philipp Deppenwiese <zaolin.daisuki@gmail.com>
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>

util/intelmetool/intelmetool.c

@@ -220,6 +220,7 @@ static int activate_me() {
 		printf("MEI not hidden on PCI, checking if visible\n");
 	}
 
+	pci_free_dev(sb);
 	pci_cleanup(pacc);
 
 	return 0;