brcm47xx: remove support for kernel 3.6

target/linux/brcm47xx/config-3.6

...atches-3.6/010-MIPS-BCM47XX-ignore-last-memory-page.patch

...-3.6/011-MIPS-BCM47XX-improve-memory-size-detection.patch

...tches-3.6/012-MIPS-BCM47xx-read-out-full-board-data.patch

...IPS-BCM47XX-read-sprom-without-prefix-if-no-ieee802.patch

...IPS-BCM47xx-sprom-read-values-without-prefix-as-fal.patch

...7xx/patches-3.6/015-MIPS-BCM47XX-remove-GPIO-driver.patch

...BCM47XX-select-GPIOLIB-for-BCMA-on-bcm47xx-platform.patch

...rcm47xx/patches-3.6/050-mtd-add-bcm47xx-part-parser.patch

...m47xx/patches-3.6/051-mtd-add-parallel-flash-driver.patch

...rcm47xx/patches-3.6/052-mtd-add-serial-flash-driver.patch

.../brcm47xx/patches-3.6/053-mtd-add-nand-flash-driver.patch

...rcm47xx/patches-3.6/060-ssb-add-serial-flash-driver.patch

.../patches-3.6/061-ssb-register-parallel-flash-device.patch

...3.6/070-bcma-add-functions-to-write-to-serial-flash.patch

...s-3.6/071-bcma-add-functions-to-write-to-nand-flash.patch

...patches-3.6/072-bcma-register-parallel-flash-device.patch

.../patches-3.6/080-MIPS-BCM47XX-rewrite-nvram-probing.patch

....6/114-MIPS-BCM47xx-Setup-and-register-serial-early.patch

...7xx/patches-3.6/116-MIPS-BCM47xx-Remove-CFE-console.patch