test: remove available memory check in setexpr_test_str_oper()

env_set() frees the previous value after allocating the new value.
As the free() may merge memory chunks the available memory is not
expected to stay constant.

Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
diff --git a/test/cmd/setexpr.c b/test/cmd/setexpr.c
index 519912a..650fbc8 100644
--- a/test/cmd/setexpr.c
+++ b/test/cmd/setexpr.c
@@ -319,7 +319,6 @@
 /* Test 'setexpr' command with concatenating strings */
 static int setexpr_test_str_oper(struct unit_test_state *uts)
 {
-	ulong start_mem;
 	char *buf;
 
 	buf = map_sysmem(0, BUF_SIZE);
@@ -327,37 +326,14 @@
 	strcpy(buf, "hello");
 	strcpy(buf + 0x10, " there");
 
-	start_mem = ut_check_free();
 	ut_asserteq(1, run_command("setexpr.s fred *0 * *10", 0));
-	ut_assertok(ut_check_delta(start_mem));
 	ut_assert_nextline("invalid op");
 	ut_assert_console_end();
 
-	/*
-	 * Set 'fred' to the same length as we expect to get below, to avoid a
-	 * new allocation in 'setexpr'. That way we can check for memory leaks.
-	 */
 	ut_assertok(env_set("fred", "12345012345"));
-	start_mem = ut_check_free();
 	ut_assertok(run_command("setexpr.s fred *0 + *10", 0));
 	ut_asserteq_str("hello there", env_get("fred"));
 
-	/*
-	 * This check does not work with sandbox_flattree, apparently due to
-	 * memory allocations in env_set().
-	 *
-	 * The truetype console produces lots of memory allocations even though
-	 * the LCD display is not visible. But even without these, it does not
-	 * work.
-	 *
-	 * A better test would be for dlmalloc to record the allocs and frees
-	 * for a particular caller, but that is not supported.
-	 *
-	 * For now, drop this test.
-	 *
-	 * ut_assertok(ut_check_delta(start_mem));
-	 */
-
 	unmap_sysmem(buf);
 
 	return 0;