Exosphere: Support unsigned/plaintext Package2s if signature is clear.

Integrate 5.x SMC API changes, add 4.x specific setup, implement target firmware selection

memcpy(x, NULL, 0) is undefined behavior

Implement BootReason config

Add most of warmboot_main

Change 'success' panic location to end of coldboot_main()

Cleanup TODOs, implement bootconfig SCR_EL3 bit setting

Implement CPU state init, fix bug in cpu_context restore

Add call to se_generate_stored_vector() before validating

Update pk2ldr outline, prepare for bootup_misc_mmio() impl

Reintroduce unmap_* in package2.c

Fix dangling comments

Fix up package2.c, current build makes it to the panic() on hardware

Rewrite relocation stuff

Implements missings parts of pk2ldr, refactor relocation a bit

Properly detect PK21 master key rev.

Fix PK2LDR bugs, Fix SE bugs

Implement flush_dcache_all_tzram_pa and invalidate_icache_all_inner_shareable_tzram_pa for the crt0s

Implement BootConfig.

Clean up SE TODOs, implement GIC nonsecure init

Rename cache.s/.h to arm.s/.h

Merge pull request #58 from MerryMage/context_id-rename ...

Rename set_core_entrypoint_and_context_id

Rewrite the memory map-related code... ...

...other style fixes, etc.

Rename set_core_entrypoint_and_context_id

Move source files to src/, add Makefile, fix all build and linkage errors, etc.