git-mailrc: Update MMC custodian

Update git-mailrc with my nick and replace afleming as mmc custodian.

Signed-off-by: Pantelis Antoniou <panto@antoniou-consulting.com>

doc/git-mailrc

@@ -24,6 +24,7 @@ alias kimphill       Kim Phillips <kim.phillips@freescale.com>
 alias macpaul        Macpaul Lin <macpaul@andestech.com>
 alias marex          Marek Vasut <marek.vasut@gmail.com>
 alias monstr         Michal Simek <monstr@monstr.eu>
+alias panto          Pantelis Antoniou <panto@antoniou-consulting.com>
 alias prafulla       Prafulla Wadaskar <prafulla@marvell.com>
 alias prom           Minkyu Kang <mk7.kang@samsung.com>
 alias rbohmer        Remy Bohmer <linux@bohmer.net>
@@ -102,7 +103,7 @@ alias cfi            uboot, stroese
 alias kerneldoc      uboot, marex
 alias fdt            uboot, Jerry Van Baren <vanbaren@cideas.com>
 alias i2c            uboot, hs
-alias mmc            uboot, afleming
+alias mmc            uboot, panto
 alias nand           uboot, scottwood
 alias net            uboot, jhersh
 alias usb            uboot, marex