tests: Move the console stubs to a dedicated directory

Move the console functions definitions out from lib/b64_decode code to
a dedicated directory.

Signed-off-by: Anna Karas <aka@semihalf.com>
Change-Id: I22a6a592f0d4d509f19920f4ad2b18e8ed83a03e
Reviewed-on: https://review.coreboot.org/c/coreboot/+/43285
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Paul Fagerburg <pfagerburg@chromium.org>
Reviewed-by: Julius Werner <jwerner@chromium.org>

tests/lib/b64_decode-test.c

@@ -24,12 +24,6 @@ const char *invalid[] = {
 	"SGVsbG-8="
 };
 
-/* Provide necessary definition in order to satisfy dependencies. */
-int do_printk(int msg_level, const char *fmt, ...)
-{
-	return 0;
-}
-
 static void test_b64_decode(void **state)
 {
 	uint8_t *decoded;