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 24 minutes and 22 seconds (queued for 7 seconds)
Status Name Job ID Coverage
  Style Check
failed check-todos #1579759
allowed to fail

00:01:20

failed style-check-diff #1579758
allowed to fail

00:01:07

 
  Build
passed cross-android_api21_arm64 #1579762

00:01:45

passed cross-android_api28_arm64 #1579763

00:03:31

passed cross-mingw64 #1579764

00:02:06

passed debian-stable-x86_64 #1579761

00:02:03

passed fedora-x86_64 #1579760

00:12:43

failed msys2-mingw32 #1579765
win32-ps

00:04:39

passed vs2017-x64 #1579766
win32-ps

00:06:58

 
  Coverage
skipped coverage #1579767
 
Name Stage Failure
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

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
msys2-mingw32 Build
GO version:   go1.13.8
Built: 2020-12-21T13:47:18+0000
OS/Arch: windows/amd64
Uploading artifacts...
Runtime platform
arch=amd64 os=windows pid=496 revision=943fc252 version=13.7.0
WARNING: _build/msys2-mingw32-report.xml: no matching files
ERROR: No files to upload
Cleaning up file based variables
ERROR: Job failed: exit status 1