MIPS: Octeon: HOTPLUG_CPU fixes.

* Rename camel-case InitTLBStart_addr to octeon_bootloader_entry_addr.

* Convert calls to cvmx_read64_uint32(), to simple pointer
  dereferences.

* Set proper ebase.

* Don't confuse coreid and cpu numbers.

* Try to maintain consistent bootloader coremask.

* Update the signature and boot_init_vector of supported bootloaders.

Signed-off-by: David Daney <ddaney@caviumnetworks.com>
To: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/1491/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>