Update paths in check tools (#1772)

In #1761, not all unit test paths have been updated in check tools.
This triggers no errors as `check-vera` emits a warning only while
`check-cppcheck` signals nothing. Still, this means that some of
the code in the repository that has been quality-assured, is now
avoiding checks. This patch fixes this.

Moreover, `check-cppcheck` has had incorrect paths for a while: it
looked for source files in the root of the repository, but those
files have been in `jerry-main` for almost a year now. This patch
fixes this, too.

Fallout of the above: `main-unix-minimal.c` had to be improved to
make `check-cppcheck` pass.

JerryScript-DCO-1.0-Signed-off-by: Akos Kiss akiss@inf.u-szeged.hu

jerry-main/main-unix-minimal.c

@@ -80,11 +80,9 @@ main (int argc,
   jerry_init (JERRY_INIT_EMPTY);
   jerry_value_t ret_value = jerry_create_undefined ();
 
-  const char *file_name;
-
   for (int i = 1; i < argc; i++)
   {
-    file_name = argv[i];
+    const char *file_name = argv[i];
     size_t source_size;
 
     const jerry_char_t *source_p = read_file (file_name, &source_size);