imx6: drop 3.12 support

target/linux/imx6/config-3.12

...ches-3.12/0001-ARM-dts-imx6qdl-add-pcie-device-node.patch

....12/0002-ARM-imx6q-Add-pll4_audio_div-to-clock-tree.patch

...3.12/0003-ARM-imx-add-soc-revision-helper-functions.patch

...3.12/0004-ARM-imx6q-use-common-soc-revision-helpers.patch

...5-ARM-imx-Add-LVDS-general-purpose-clocks-to-i.MX6Q.patch

...ARM-imx6q-clock-and-Kconfig-update-for-PCIe-support.patch

...12/0007-ARM-dts-added-several-new-imx-pinmux-groups.patch

...hes-3.12/0008-ARM-dts-add-Gateworks-Ventana-support.patch

...09-imx-add-PCI-fixup-for-PEX860X-on-Gateworks-board.patch

...10-ARM-imx6q-Add-PCIe-bits-to-GPR-syscon-definition.patch

...0011-PCI-imx6-Add-support-for-i.MX6-PCIe-controller.patch

.../patches-3.12/0030-pcie-designware-fix-io-transfers.patch

.../imx6/patches-3.12/0031-PCI-imx6-init-must-be-early.patch

...ches-3.12/0032-PCI-imx6-fix-imprecise-abort-handler.patch

...x6/patches-3.12/0033-PCI-imx6-increase-link-startup.patch

...ches-3.12/0034-PCI-imx6-add-support-for-legacy-irqs.patch

...t/linux/imx6/patches-3.12/0040-i2c-imx-retry-on-NAK.patch

...x6/patches-3.12/0050-sky2-allow-mac-to-come-from-dt.patch

target/linux/imx6/patches-3.12/100-bootargs.patch