Fix GCC warning

    ../tests/check_dicom.c: In function ‘test_element_CS_multivalue_empty_fn’:
    ../tests/check_dicom.c:306:21: warning: allocation of insufficient size ‘1’ for type ‘char *’ with size ‘8’ [-Walloc-size]

Author: bgilbert

tests/check_dicom.c

@@ -303,7 +303,7 @@ START_TEST(test_element_CS_multivalue_empty)
     uint32_t vm = 0;
 
     // since malloc(0) can be NULL on some platforms
-    char **values = malloc(1);
+    char **values = malloc(sizeof(char *));
 
     DcmElement *element = dcm_element_create(NULL, tag, DCM_VR_CS);
     (void) dcm_element_set_value_string_multi(NULL, element, values, vm, true);