disable mail for swarren

I haven't been involved in U-Boot development for quite a while, so
CCing me on patches isn't currently useful. Add a .mailmap entry that I
believe will turn off patch CCs. This can always be removed if I become
active again! Remove myself from a few MAINTAINERS failed and the git
mailrc file too.
diff --git a/.mailmap b/.mailmap
index 5c48114..830a263 100644
--- a/.mailmap
+++ b/.mailmap
@@ -127,6 +127,8 @@
 Stefan Roese <sr@denx.de> <stroese>
 Stefano Babic <sbabic@nabladev.com>
 Stefano Stabellini <stefano.stabellini@amd.com> <stefano.stabellini@xilinx.com>
+No generic patch CC mail please <noreply@example.com> <swarren@wwwdotorg.org>
+No generic patch CC mail please <noreply@example.com> <swarren@nvidia.com>
 Sumit Garg <sumit.garg@kernel.org> <sumit.garg@linaro.org>
 Tom Rini <trini@konsulko.com> <trini@ti.com>
 Tomas Thoresen <tomas.thoresen@amd.com> <tomast@xilinx.com>