lttng-ust: update to 2.12.2.

Move to python_version=3. Using py2 was ok, since the lttng-gen-tp
script supported both, but it's supported py3 since [1].

[1] 2d9c7df199

Closes: #31190 [via git-merge-pr]

srcpkgs/lttng-ust/template

@@ -1,6 +1,6 @@
 # Template file for 'lttng-ust'
 pkgname=lttng-ust
-version=2.12.0
+version=2.12.2
 revision=1
 build_style=gnu-configure
 makedepends="liburcu-devel libnuma-devel"
@@ -11,8 +11,8 @@ license="LGPL-2.1-only"
 homepage="http://lttng.org"
 changelog="https://github.com/lttng/lttng-ust/raw/master/ChangeLog"
 distfiles="${homepage}/files/${pkgname}/${pkgname}-${version}.tar.bz2"
-checksum=1983edb525f3f27e3494088d8d5389b4c71af66bbfe63c6f1df2ad95aa44a528
-python_version=2 #unverified
+checksum=bcd0f064b6ca88c72d84e760eac3472ae5c828411c634435922bee9fce359fc7
+python_version=3
 
 lttng-ust-devel_package() {
 	depends="${sourcepkg}>=${version}_${revision} liburcu-devel"