tests: Add lib/malloc-test test case

Signed-off-by: Jakub Czapiga <jacz@semihalf.com>
Change-Id: Ic6b10ec382cc807772689e852bad300c75da1fe2
Reviewed-on: https://review.coreboot.org/c/coreboot/+/50715
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Paul Fagerburg <pfagerburg@chromium.org>

tests/lib/Makefile.inc

@@ -18,6 +18,7 @@ tests-y += memset-test
 tests-y += memcmp-test
 tests-y += memchr-test
 tests-y += memcpy-test
+tests-y += malloc-test
 
 string-test-srcs += tests/lib/string-test.c
 string-test-srcs += src/lib/string.c
@@ -91,3 +92,6 @@ memchr-test-srcs += src/lib/memchr.c
 
 memcpy-test-srcs += tests/lib/memcpy-test.c
 
+malloc-test-srcs += tests/lib/malloc-test.c
+malloc-test-srcs += tests/stubs/console.c
+