.mailmap: Correct entires for Masahiro Yamada

His entries had the correct email address listed last rather than first,
correct this.

Fixes 4fa4227c (".mailmap: Record all address for main U-Boot contributor")
Signed-off-by: Tom Rini <trini@konsulko.com>
Acked-by: Michal Simek <michal.simek@amd.com>