MAINTAINERS: update Socionext SPI maintainer address

The Linaro address is bouncing so switch to Masahisa's Socionext address
also found in MAINTAINERS.

Acked-by: Masahisa Kojima <kojima.masahisa@socionext.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://patch.msgid.link/20260410083423.504695-2-johan@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>

Author: jhovold

MAINTAINERS

@@ -24465,7 +24465,7 @@ F:	Documentation/devicetree/bindings/net/socionext,synquacer-netsec.yaml
 F:	drivers/net/ethernet/socionext/netsec.c
 
 SOCIONEXT (SNI) Synquacer SPI DRIVER
-M:	Masahisa Kojima <masahisa.kojima@linaro.org>
+M:	Masahisa Kojima <kojima.masahisa@socionext.com>
 M:	Jassi Brar <jaswinder.singh@linaro.org>
 L:	linux-spi@vger.kernel.org
 S:	Maintained