Make kernel log buffer derived from cmake config

This removes the explicit CMake configuration for the kernel log buffer
and replaces it with a #define that is enabled for the required
configurations.

Signed-off-by: Curtis Millar <curtis@curtism.me>

Convert license tags to SPDX identifiers

This commit also converts our own copyright headers to directly use
SPDX, but leaves all other copyright header intact, only adding the
SPDX ident. As far as possible this commit also merges multiple
Data61 copyright statements/headers into one for consistency.

ia32: remove unsued ia32KSGlobalPDPT and PDPT defines

SELFOUR-630:preliminary booting application processors
- update core detection code and Kconfig file
- update kernel stack managment so that BSP does not use boot stack before IPI APs
- move arch dependant data to a single structure
- add cache line size to Kconfig
- add cpu indexing and apic id mapping
- boot APs to halting state
- add guard for kernel stack if there is only one core

Revert "Merge pull request #358 in SEL4/sel4 from ~AZARRABI/sel4:multicore to master"

This reverts commit ce2f666bb811c5e4c779829fcb09d5a189ebcdbb, reversing
changes made to dc183f96b81f2344d7d0d910fc430f924eaae940.

SELFOUR-630:preliminary booting application processors
- update core detection code and Kconfig file
- update kernel stack managment so that BSP does not use boot stack before IPI APs
- move arch dependant data to a single structure
- add cache line size to Kconfig
- add cpu indexing and apic id mapping
- boot APs to halting state
- add guard for kernel stack if there is only one core

SELFOUR-556: Rationalize BITS vs INDEX_BITS

s/PD_BITS/PD_INDEX_BITS
Current convention is to say that X_BITS is the log base 2
size of an object, not the log base 2 number of indices

SELFOUR-556: Rationalize BITS vs INDEX_BITS

s/PT_BITS/PT_INDEX_BITS
Current convention is to say that X_BITS is the log base 2
size of an object, not the log base 2 number of indices

SELFOUR-556: Rationalize BITS vs INDEX_BITS

s/PDT_BITS/PDPT_INDEX_BITS
Current convention is to say that X_BITS is the log base 2
size of an object, not the log base 2 number of indices

SELFOUR-518: User-level log buffer

Remove global ksLog and use KS_LOG_PPTR instead

Benchmark - Log buffer: use global page table

SELFOUR-399: object sizes and globals frame addr should come from the same source

x86: Create 32-bit specific statedata