Rename libpcre.wrap to pcre.wrap

It is exactly the same wrap as the one in WrapDB but with a different
name. That fix error when multiple projects uses pcre and they don't
have the same wrap name:

meson.build:1:0: ERROR: Multiple wrap files provide 'libpcre' dependency: pcre.wrap and libpcre.wrap
10 jobs for pcre in 29 minutes and 25 seconds (queued for 5 seconds)
Status Name Job ID Coverage
  Style Check
failed check-todos #1595508
allowed to fail

00:01:57

failed style-check-diff #1595507
allowed to fail

00:01:43

 
  Build
passed cross-android_api21_arm64 #1595511

00:01:29

passed cross-android_api28_arm64 #1595512

00:03:12

passed cross-mingw64 #1595513

00:03:25

passed debian-stable-x86_64 #1595510

00:02:42

passed fedora-x86_64 #1595509

00:09:25

passed msys2-mingw32 #1595514
win32-ps

00:12:52

passed vs2017-x64 #1595515
win32-ps

00:07:06

 
  Coverage
passed coverage #1595516

00:02:01

76.2%
 
Name Stage Failure
failed
check-todos Style Check
 * branch                pcre       -> FETCH_HEAD
fatal: ambiguous argument 'upstream/master': unknown revision or path not in the working tree.
Use '--' to separate paths from revisions, like this:
'git <command> [<revision>...] -- [<file>...]'
Couldn’t find common ancestor with upstream main branch. This typically
happens if you branched from main a long time ago. Please update
your clone, rebase, and re-push your branch.
Cleaning up project directory and file based variables
ERROR: Job failed: exit code 1

failed
style-check-diff Style Check
 * branch                pcre       -> FETCH_HEAD
fatal: ambiguous argument 'upstream/master': unknown revision or path not in the working tree.
Use '--' to separate paths from revisions, like this:
'git <command> [<revision>...] -- [<file>...]'
Couldn’t find common ancestor with upstream main branch. This typically
happens if you branched from main a long time ago. Please update
your clone, rebase, and re-push your branch.
Cleaning up project directory and file based variables
ERROR: Job failed: exit code 1