Module api tests for RM_Call

Adding a test for coverage for RM_Call in a new "misc" unit
to be used for various short simple tests

also solves compilation warnings in redismodule.h and fork.c

tests/unit/moduleapi/misc.tcl

@@ -0,0 +1,19 @@
+set testmodule [file normalize tests/modules/misc.so]
+
+
+start_server {tags {"modules"}} {
+    r module load $testmodule
+
+    test {test RM_Call} {
+        set info [r test.call_info commandstats]
+        # cmdstat is not in a default section, so we also test an argument was passed
+        assert { [string match "*cmdstat_module*" $info] }
+    }
+
+    test {test RM_Call args array} {
+        set info [r test.call_generic info commandstats]
+        # cmdstat is not in a default section, so we also test an argument was passed
+        assert { [string match "*cmdstat_module*" $info] }
+    }
+
+}