target/octeon: Add Linux 4.19 support

target/octeon: Add Linux 4.19 support

This commit adds support for Linux 4.19 kernel, various cleanups
listed below.

Drop 170-cisco-hack.patch as these devices never seems to have been
supported.

Unset kernel symbols:

* CONFIG_CAVIUM_CN63XXP1=y
  No supported hardware uses CN63XXP1 and it causes "slight decrease in
  performance"
  Source: https://cateee.net/lkddb/web-lkddb/CAVIUM_CN63XXP1.html

* CONFIG_USB_OCTEON_EHCI=y
  CONFIG_USB_OCTEON_OHCI=y
  Deprecated
  Source: https://cateee.net/lkddb/web-lkddb/USB_OCTEON_EHCI.html
  https://cateee.net/lkddb/web-lkddb/USB_OCTEON_OHCI.html

Removed kernel symbols:

* # CONFIG_ARCH_HIBERNATION_POSSIBLE=y
* CONFIG_ARCH_SUSPEND_POSSIBLE=y
  These are not in if you do a vanilla config of a MIPS Octeon kernel
  and I can't find any references about support on this platform.

* # CONFIG_BOOTPARAM_HUNG_TASK_PANIC is not set
* CONFIG_BOOTPARAM_HUNG_TASK_PANIC_VALUE=0
  No need to have this in by default, not defined in most other targets

* CONFIG_CRASH_CORE=y
  Can't find any documentation why this should be enabled by default

* CONFIG_DEBUG_INFO=y
  Set by https://github.com/openwrt/openwrt/blob/master/config/Config-kernel.in#L134

* CONFIG_DEBUG_SPINLOCK=y
  No need to have this in by default

* CONFIG_DEFAULT_HUNG_TASK_TIMEOUT=120
  Already set by default
  Source: https://cateee.net/lkddb/web-lkddb/DEFAULT_HUNG_TASK_TIMEOUT.html

* CONFIG_DETECT_HUNG_TASK=y
  No need to have this in by default, not defined in most other targets

* CONFIG_HAVE_DEBUG_KMEMLEAK=y
  No need to have this in by default, not defined in most other targets

* CONFIG_HAVE_DEBUG_STACKOVERFLOW=y
  No need to have this in by default

* CONFIG_HAVE_IDE=y
  None of the supported devices have IDE

* CONFIG_HZ=250
* # CONFIG_HZ_100 is not set
* CONFIG_HZ_250=y
  This is broken with generic config

* CONFIG_KALLSYMS=y
  No need to have this in by default, not defined in most other targets

* CONFIG_KEXEC=y
* CONFIG_KEXEC_CORE=y
  No need to have this in by default, not defined in most other targets

* CONFIG_HAVE_KVM=y
  No need to have this in by default

* CONFIG_SCHED_DEBUG=y
  No need to have this in by default, not defined in most other targets

* CONFIG_SYSFS_DEPRECATED=y
  Deprecated symbol
  Source: https://cateee.net/lkddb/web-lkddb/SYSFS_DEPRECATED.html

* CONFIG_SYSFS_DEPRECATED_V2=y
  Discouraged usage in general
  Source: https://cateee.net/lkddb/web-lkddb/SYSFS_DEPRECATED_V2.html

* CONFIG_UNINLINE_SPIN_UNLOCK=y
  No need to have this in by default, not defined in most other targets
  Source: https://github.com/openSUSE/kernel/blob/master/lib/Kconfig.debug#L1137

* CONFIG_ZLIB_INFLATE=y
  No need to have this in by default, not defined in most other targets

Signed-off-by: Daniel Engberg <daniel.engberg.lists@pyret.net>