Revert "python/build/libs.py: remove flac, switch to Meson wrap"

This reverts commit 6ed4aff4d3.  The
Meson wrap is broken on non-x86, because it unconditionally includes
<cpuid.h> which is an x86 only header.

subprojects/.gitignore

@@ -1,7 +1,6 @@
 /packagecache/
 
 /expat-*/
-/flac-*/
 /fmt-*/
 /googletest-*/
 /sqlite-*/

subprojects/flac.wrap

@@ -1,12 +0,0 @@
-[wrap-file]
-directory = flac-1.3.3
-source_url = https://github.com/xiph/flac/archive/refs/tags/1.3.3.tar.gz
-source_filename = 1.3.3.tar.gz
-source_hash = 668cdeab898a7dd43cf84739f7e1f3ed6b35ece2ef9968a5c7079fe9adfe1689
-patch_url = https://wrapdb.mesonbuild.com/v1/projects/flac/1.3.3/1/get_zip
-patch_filename = flac-1.3.3-1-wrap.zip
-patch_hash = bcd79061d1d29f8871646a356eb15ee2b6bacdc960594f584dcd4f90d7e0d4dd
-
-[provide]
-flac = flac_dep
-