mailmap: Canonicalize to Qais' current email address.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

.mailmap

@@ -125,6 +125,7 @@ Peter Oruba <peter@oruba.de>
 Peter Oruba <peter.oruba@amd.com>
 Pratyush Anand <pratyush.anand@gmail.com> <pratyush.anand@st.com>
 Praveen BP <praveenbp@ti.com>
+Qais Yousef <qsyousef@gmail.com> <qais.yousef@imgtec.com>
 Rajesh Shah <rajesh.shah@intel.com>
 Ralf Baechle <ralf@linux-mips.org>
 Ralf Wildenhues <Ralf.Wildenhues@gmx.de>