Two small patches to armv7m_load_kernel(). The first is just getting
rid of some dead code, that I noticed while working on the function.
The second is to make boards pass armv7m_load_kernel() the base
address for loading guest (non-ELF) binaries. At the moment we
assume all M-profile boards start at address 0; this happens to be
true for all the ones we implement right now, but it's not true in
general. In particular the Teeny board has its ROM at 0x0020_0000.
I thought about having armv7m_load_kernel() be "clever" and ask the
CPU what init-svtor/init-nsvtor were set to, but that seems like it
might have unanticipated consequences[*]. "Just pass the base address"
is simpler and is how A-profile does it (though for A-profile it's
the loader_start field in struct arm_boot_info rather than an extra
argument).
[*] eg where the board has the rom/flash aliased at both address
0 and some other address, and init-svtor points at an alias;
also Secure vs NonSecure address spaces and loading...