dev-python/pyudev: Replace python_gen_usedep with python_gen_cond_dep

An upgrade attempt was made in CL:2329159, but it fails because of
reverse depedencies that want python 2* support.

BUG=chromium:1111336
TEST=emerge pyudev

Change-Id: Ia1d198bab7f72744fa8ba70050e05ce9c530a9cb
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/overlays/portage-stable/+/2333114
Tested-by: Allen Webb <allenwebb@google.com>
Auto-Submit: Allen Webb <allenwebb@google.com>
Commit-Queue: Allen Webb <allenwebb@google.com>
Commit-Queue: Alex Klein <saklein@chromium.org>
Reviewed-by: Alex Klein <saklein@chromium.org>
diff --git a/dev-python/pyudev/pyudev-0.21.0-r1.ebuild b/dev-python/pyudev/pyudev-0.21.0-r1.ebuild
new file mode 120000
index 0000000..a2a70cb
--- /dev/null
+++ b/dev-python/pyudev/pyudev-0.21.0-r1.ebuild
@@ -0,0 +1 @@
+pyudev-0.21.0.ebuild
\ No newline at end of file
diff --git a/dev-python/pyudev/pyudev-0.21.0.ebuild b/dev-python/pyudev/pyudev-0.21.0.ebuild
index 5448119..a0f474c 100644
--- a/dev-python/pyudev/pyudev-0.21.0.ebuild
+++ b/dev-python/pyudev/pyudev-0.21.0.ebuild
@@ -19,7 +19,7 @@
 RDEPEND="
 	dev-python/six[${PYTHON_USEDEP}]
 	virtual/udev
-	pygobject? ( dev-python/pygobject:2[$(python_gen_usedep 'python2*')] )
+	pygobject? ( $(python_gen_cond_dep 'dev-python/pygobject:2[${PYTHON_USEDEP}]' 'python2*') )
 	qt5? ( dev-python/PyQt5[${PYTHON_USEDEP}] )
 "
 DEPEND="${RDEPEND}