target-rl78: Add initial stubs for RL78

Add support for {78k0,rl78}-softmmu in configure.
Stub out target-78k0/, hw/78k0/ and hw/rl78/.

Signed-off-by: Andreas Färber <andreas.faerber@web.de>
rl78: Prepare Renesas RL78/G13 Promotion Board

Set up RAM and code flash.

Signed-off-by: Andreas Färber <andreas.faerber@web.de>
target-rl78: Add ELF machine identifier

Signed-off-by: Andreas Färber <andreas.faerber@web.de>
rl78: Load BIOS

Signed-off-by: Andreas Färber <andreas.faerber@web.de>
target-rl78: Flesh out disas

Signed-off-by: Andreas Färber <andreas.faerber@web.de>
target-rl78: Implement CPU reset

Signed-off-by: Andreas Färber <andreas.faerber@web.de>
target-rl78: Implement tlb_fill()

Signed-off-by: Andreas Färber <andreas.faerber@web.de>
target-rl78: Add calls to gen_io_{start,end}()

Signed-off-by: Andreas Färber <andreas.faerber@web.de>
target-rl78: Add call to tcg_gen_debug_insn_start()

Signed-off-by: Andreas Färber <andreas.faerber@web.de>
target-rl78: Update PC

Signed-off-by: Andreas Färber <andreas.faerber@web.de>
rl78: Defer CPU realization til after BIOS is loaded

On reset the CPU needs to load PC from memory.
Therefore inline cpu_rl78_init() into machine init.

Signed-off-by: Andreas Färber <andreas.faerber@web.de>
target-rl78: Load reset vector to PC

Inspired by ARM M profile. Thanks to Peter for suggesting.

Signed-off-by: Andreas Färber <andreas.faerber@web.de>
target-rl78: Implement MOV !addr16,#byte

Signed-off-by: Andreas Färber <andreas.faerber@web.de>
rl78: Add SFR MemoryRegion

Signed-off-by: Andreas Färber <andreas.faerber@web.de>
rl78: Add MemoryRegion for GPRs

Signed-off-by: Andreas Färber <andreas.faerber@web.de>
target-rl78: Implement MOVW sfrp,#word

This is the first instruction of GCC-generated _start, thus starting to
make target-rl78 "usable".

Signed-off-by: Andreas Färber <andreas.faerber@web.de>
target-rl78: Prepare SP

Prepare TCG variable and add to info output.

Signed-off-by: Andreas Färber <andreas.faerber@web.de>
target-rl78: Implement MOV ES,#byte

Introduce ES and CS.

Signed-off-by: Andreas Färber <andreas.faerber@web.de>
target-rl78: Prepare 2nd MAP

Signed-off-by: Andreas Färber <andreas.faerber@web.de>
target-rl78: Prepare PSW

Signed-off-by: Andreas Färber <andreas.faerber@web.de>