MAINTAINERS: change my e-mail address for at24

I now do this as part of my work for BayLibre. Change the address
to my professional one.

Signed-off-by: Bartosz Golaszewski <[e-mail]>

MAINTAINERS

···
 F:	include/linux/async_tx.h
 
 AT24 EEPROM DRIVER
-M:	Bartosz Golaszewski <[e-mail]>
+M:	Bartosz Golaszewski <[e-mail]>
 L:	[e-mail]
 T:	git git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux.git
 S:	Maintained