Ignore -Werror

In some cases Clang is stricter than GCC regarding the warning messages.
-Werror flag converts these to error messages which thus fail the
analysis. That's why -Werror will be ignored from now on.

libcodechecker/log/option_parser.py

@@ -134,7 +134,11 @@
     '-sectorder': 3,
     '--param': 1,
     '-u': 1,
-    '--serialize-diagnostics': 1
+    '--serialize-diagnostics': 1,
+    # If Clang gives warning on which GCC doesn't then during checking it is
+    # considered an error and fails the analysis if the original build contains
+    # -Werror flag.
+    '-Werror': 0
 }
 
 IGNORED_OPTION_MAP_REGEX = {