x86: remove support for old kernels

target/linux/x86/alix2/config-default

target/linux/x86/config-3.2

target/linux/x86/config-default

target/linux/x86/ep80579/config-default

target/linux/x86/generic/config-default

target/linux/x86/geos/config-3.3

target/linux/x86/kvm_guest/config-default

target/linux/x86/net5501/config-default

target/linux/x86/olpc/config-default

target/linux/x86/patches-3.2/001-alix_platform.patch

target/linux/x86/patches-3.2/002-geos_platform.patch

target/linux/x86/patches-3.2/005-net5501_platform.patch

target/linux/x86/patches-3.2/901-8139cp_eeprom_delay.patch

target/linux/x86/patches-3.2/902-8139cp_config_rx_mode.patch

target/linux/x86/thincan/config-default

target/linux/x86/xen_domu/config-default