ARM: mvebu: re-enable SDHCI driver for Armada 38x SoC in v7 defconfig

In the recent update of mvebu_v7_defconfig a config that enables sdhci-pxav3
driver, that supports SDHCI interface of Armada 38x SoC, disappeared.

This commit enables CONFIG_MMC_SDHCI_PXAV3 back.
Signed-off-by: NMarcin Wojtas <mw@semihalf.com>
Reviewed-by: NGregory CLEMENT <gregory.clement@free-electrons.com>
Acked-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>
Acked-by: NAndrew Lunn <andrew@lunn.ch>
Fixes fc9fa871 ("ARM: mvebu: update v7 defconfig with useful options")
Link: https://lkml.kernel.org/r/1415980652-7429-2-git-send-email-mw@semihalf.comSigned-off-by: NJason Cooper <jason@lakedaemon.net>

arch/arm/configs/mvebu_v7_defconfig

@@ -100,6 +100,7 @@ CONFIG_MMC=y
 CONFIG_MMC_SDHCI=y
 CONFIG_MMC_SDHCI_PLTFM=y
 CONFIG_MMC_SDHCI_DOVE=y
+CONFIG_MMC_SDHCI_PXAV3=y
 CONFIG_MMC_MVSDIO=y
 CONFIG_LEDS_GPIO=y
 CONFIG_LEDS_CLASS=y