test: Drop the _test suffix on linker lists

Most test suites have a _test suffix. This is not necessary as there is
also a ut_ prefix.

Drop the suffix so that (with future work) the suite name can be used as
the linker-list name.

Remove the suffix from the pytest regex as well, moving it to the top of
the file, as it is a constant.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/test/cmd/mem_copy.c b/test/cmd/mem_copy.c
index 67eca32..3e904fc 100644
--- a/test/cmd/mem_copy.c
+++ b/test/cmd/mem_copy.c
@@ -12,7 +12,7 @@
 #define BUF_SIZE	256
 
 /* Declare a new mem test */
-#define MEM_TEST(_name)	UNIT_TEST(_name, 0, mem_test)
+#define MEM_TEST(_name)	UNIT_TEST(_name, 0, mem)
 
 struct param {
 	int d, s, count;