Tighten the bounds used in IS_OUT_OF_BOUNDS; j must be a valid index
into the input buffer, but the current code allows j to be -1 in the
reverse QS case.
Remove an incorrect cast from my last commit.
Check j <= 0 instead of j - 1 < 0.
Revert half of my last change. It the case of a matching a fixed string
in a line where the string has a non-empty prefix and empty suffix.
Merge branch 'bsdgrep-rqs-crash' into markj

Conflicts:
	usr.bin/grep/regex/tre-fastmatch.c