check-code: drop now unused check-code-ignore

Using check-code-ignore to skip the failures on a line has several
disadvantages:
 * It skips all check-code failures on a line, not only the one it was created
   for.
 * It does not give any hint for which rule it was added, making it difficult to
   see when it is not needed anymore.
So drop this pragma in favor of better alternatives promoted before.

contrib/check-code.py

@@ -494,12 +494,7 b' def checkfile(f, logfunc=_defaultlogger.'
                     n += 1
                 l = prelines[n]
 
-                if "check-code" "-ignore" in l:
-                    if debug:
-                        print "Skipping %s for %s:%s (check-code" "-ignore)" % (
-                            name, f, n)
-                    continue
-                elif ignore and re.search(ignore, l, re.MULTILINE):
+                if ignore and re.search(ignore, l, re.MULTILINE):
                     continue
                 bd = ""
                 if blame: