ARM i.MX6: Fix bootsource detection

This patch fixes boot_mode detection for non-internal boot and
bootsource detection for i2c boot. Further, the bootsouce_instance
is now determined for spi, i2c, and mmc/sd boot.

Signed-off-by: Philipp Zabel <philipp.zabel@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
ARM: i.MX53: tqma53: fix board name in Kconfig

Signed-off-by: Markus Niebel <Markus.Niebel@tqs.de>
Signed-off-by: Steffen Trumtrar <s.trumtrar@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
ARM: i.MX53: tqma53: move RAM setting to submenu

Signed-off-by: Markus Niebel <Markus.Niebel@tqs.de>
Signed-off-by: Steffen Trumtrar <s.trumtrar@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
ARM: i.MX53: tqma53: update flash_header

Integrate errata fixes for SDCTL settings.

Signed-off-by: Markus Niebel <Markus.Niebel@tqs.de>
Signed-off-by: Steffen Trumtrar <s.trumtrar@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>