mailmap: update Nick's entry

Link: https://lkml.kernel.org/r/20250211212117.3195265-1-ndesaulniers@google.com
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Author: nickdesaulniers

.mailmap

@@ -534,6 +534,7 @@ Nicholas Piggin <npiggin@gmail.com> <npiggin@kernel.dk>
 Nicholas Piggin <npiggin@gmail.com> <npiggin@suse.de>
 Nicholas Piggin <npiggin@gmail.com> <nickpiggin@yahoo.com.au>
 Nicholas Piggin <npiggin@gmail.com> <piggin@cyberone.com.au>
+Nick Desaulniers <nick.desaulniers+lkml@gmail.com> <ndesaulniers@google.com>
 Nicolas Ferre <nicolas.ferre@microchip.com> <nicolas.ferre@atmel.com>
 Nicolas Pitre <nico@fluxnic.net> <nicolas.pitre@linaro.org>
 Nicolas Pitre <nico@fluxnic.net> <nico@linaro.org>