Hexagon (target/hexagon) Change Hexagon maintainer

Change Hexagon maintainer from Taylor Simpson to Brian Cain
Put Taylor's gmail address in .mailmap

Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org
Message-Id: <20230524165355.3157700-2-tsimpson@quicinc.com>
diff --git a/MAINTAINERS b/MAINTAINERS
index 1c93ab0..4b025a7 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -218,7 +218,7 @@
 F: disas/cris.c
 
 Hexagon TCG CPUs
-M: Taylor Simpson <tsimpson@quicinc.com>
+M: Brian Cain <bcain@quicinc.com>
 S: Supported
 F: target/hexagon/
 X: target/hexagon/idef-parser/