waf: Enable Werror by default and add option to disable it

Signed-off-by: Ryan Friedman <ryanfriedman5410+github@gmail.com>

wscript

@@ -143,9 +143,14 @@ def options(opt):
 
     g.add_option('--Werror',
         action='store_true',
-        default=False,
+        default=True,
         help='build with -Werror.')
 
+    g.add_option('--disable-Werror',
+        action='store_true',
+        default=False,
+        help='Disable -Werror.')
+    
     g.add_option('--toolchain',
         action='store',
         default=None,
@@ -584,6 +589,12 @@ def configure(cfg):
     # Always use system extensions
     cfg.define('_GNU_SOURCE', 1)
 
+    if cfg.options.Werror:
+        if cfg.options.disable_Werror:
+            raise ValueError("Cannot enable and disable Werror at the same time")
+        else:
+            cfg.options.Werror = not cfg.options.disable_Werror
+
     cfg.write_config_header(os.path.join(cfg.variant, 'ap_config.h'), guard='_AP_CONFIG_H_')
 
     # add in generated flags