go.buildinfo is about 0.5 KB and placed in Segdata (not Segrodata) so
it takes RAM and Flash. Including it is to expensive on GOOS=noos.

This file was created during the merge of go1.20.5 into embedded and
seems to be a copy of `ssa.go` with some minor modifications.

It works unrealiable and causes objdump test fails for GOARCH=arm in case of
the PIE or the external linking. For now the thumb disassembler runs for ARM
binaries if GOARCH == "thumb".

Add mising stubs for vars, types and functions for cgo, mprof and scavenger.

Only minimal set of most popular functions and interfaces are implemented.

Current implementation of riscv64 memmove in Go handles unaligned
accesses properly so the Kendryte specific implementation can
be removed.

Reseting the state of maximum possible number of PLIC contexts and interupts
causes exception on the QEMU virt machine. Reduce the number of supported
contexts to 8 which match the maximum number for virt. It doesn't affect the
Kendryte K210.

The RISCV spec says that reading from the mepc register should always
return a value with the bit0 = 0, even for implicit reads by MRET.

QEMU 8.2 always returns an unmodified value and what worse it doesn't
raise the Instruction address misaligned exception if the C (compressed
instructions) extension is enabled.

Use SYS_EXIT_EXTENDED instead of SYS_EXIT in thumb code to support the
return value.

Properly set field 1 to ADP_Stopped_ApplicationExit in riscv64 code.