test/cfg: Improved testing of std.cfg regarding uninitialized variables.

cfg/std.cfg

@@ -2866,7 +2866,7 @@
     </arg>
   </function>
   <!-- wchar_t wcscat(wchar_t *deststr, const char *srcstr); -->
-  <function name="wcscat">
+  <function name="wcscat,std::wcscat">
     <noreturn>false</noreturn>
     <leak-ignore/>
     <arg nr="1">

test/cfg/std.c

@@ -2780,3 +2780,19 @@ void uninivar_setvbuf(void)
     // cppcheck-suppress uninitvar
     (void)setvbuf(stream,buf,mode,size);
 }
+
+void uninivar_strcat(void)
+{
+    char *deststr;
+    char *srcstr;
+    // cppcheck-suppress uninitvar
+    (void)strcat(deststr,srcstr);
+}
+
+void uninivar_wcscat(void)
+{
+    wchar_t *deststr;
+    wchar_t *srcstr;
+    // cppcheck-suppress uninitvar
+    (void)wcscat(deststr,srcstr);
+}

test/cfg/std.cpp

@@ -2104,3 +2104,19 @@ void uninivar_setvbuf(void)
     // cppcheck-suppress uninitvar
     (void)std::setvbuf(stream,buf,mode,size);
 }
+
+void uninivar_strcat(void)
+{
+    char *deststr;
+    char *srcstr;
+    // cppcheck-suppress uninitvar
+    (void)std::strcat(deststr,srcstr);
+}
+
+void uninivar_wcscat(void)
+{
+    wchar_t *deststr;
+    wchar_t *srcstr;
+    // cppcheck-suppress uninitvar
+    (void)std::wcscat(deststr,srcstr);
+}