grep/pcre2: use PCRE2_UTF even with ASCII patterns
compile_pcre2_pattern() currently uses the option PCRE2_UTF only for
patterns with non-ASCII characters. Patterns with ASCII wildcards can
match non-ASCII strings, though. Without that option PCRE2 mishandles
UTF-8 input, though -- it matches parts of multi-byte characters. Fix
that by using PCRE2_UTF even for ASCII-only patterns.
This is a remake of the reverted
ae39ba431a (grep/pcre2: fix an edge
case concerning ascii patterns and UTF-8 data, 2021-10-15). The change
to the condition and the test are simplified and more targeted.
Original-patch-by: Hamza Mahfooz <someguy@effective-light.com>
Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>