DEVELOPERS: drop libqrtr-glib from Yegor Yefremov

Commit 73ce754531 in master added  the
libqrtr-glib package to Yegor Yefremov.

This commit was backported as fad154253d
in the LTS 2021.02.x branch, but this branch does not have the
libqrtr-glib package, as it was added after 2021.02.

Due to this, the DEVELOPERS file is bogus in 2021.02.x, which causes
the following warning when running pkg-stats:

WARNING: 'package/libqrtr-glib/' doesn't match any file

This commit fixes this by dropping the bogus line from the DEVELOPERS
file.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

DEVELOPERS

@@ -2755,7 +2755,6 @@ F:	package/libmbim/
 F:	package/libndp/
 F:	package/libnftnl/
 F:	package/libqmi/
-F:	package/libqrtr-glib/
 F:	package/libsoc/
 F:	package/libsocketcan/
 F:	package/libubox/