Add and fix copyright notices for better GPL compliance (thanks @naehrwert and @CTCaer).

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

Fix fuse_get_hardware_type for 4.x

Add TI charger stuff to warmboot_main, add 4.x hw_type stuff as well

Implement half of bootup_misc_mmio()

Implement a few TODOs with CAR driver.

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

...other style fixes, etc.

fuse: simplify checks in fuse_get_reserved_odm and fuse_get_spare_bit (#54) ...

A separate variable isn't particularly necessary here, and given that the type
is unsigned, we only need to test the upper bound.

This also resolves two -Wtype-limits warnings

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