bug#35626: Beef up "conflicting matchers specified" error message

[積丹尼 Dan Jacobson]

$ egrep -P '\t|_|  '
grep: conflicting matchers specified

The user scratches his head and thinks "was it the \t, the _ or the '  '?"

After testing each one he finally looks on the man page where the answer
is obvious.

But wouldn't it save his time if the error said at least:
$ egrep -P '\t|_|  '
grep: conflicting matchers specified: -P