MAINTAINERS: fix Pantelis Antoniou email address

Trivial fix (unless Pantelis has a new email address):

Pantelis Antoniou <panto.antoniou-consulting.com>
                        ^
make it:
Pantelis Antoniou <panto@antoniou-consulting.com>

Signed-off-by: Igor Grinberg <grinberg@compulab.co.il>
Cc: Pantelis Antoniou <panto@antoniou-consulting.com>

MAINTAINERS

@@ -253,7 +253,7 @@ T:	git git://git.denx.de/u-boot-mips.git
 F:	arch/mips/
 
 MMC
-M:	Pantelis Antoniou <panto.antoniou-consulting.com>
+M:	Pantelis Antoniou <panto@antoniou-consulting.com>
 S:	Maintained
 T:	git git://git.denx.de/u-boot-mmc.git
 F:	drivers/mmc/