esirisc: support eSi-RISC targets

eSi-RISC is a highly configurable microprocessor architecture for
embedded systems provided by EnSilica. This patch adds support for
32-bit targets and also includes an internal flash driver and
uC/OS-III RTOS support. This is a non-traditional target and required
a number of additional changes to support non-linear register numbers
and the 'p' packet in RTOS support for proper integration into
EnSilica's GDB port.

Change-Id: I59d5c40b3bb2ace1b1a01b2538bfab211adf113f
Signed-off-by: Steven Stallion <stallion@squareup.com>
Reviewed-on: http://openocd.zylin.com/4660
Tested-by: jenkins
Reviewed-by: Matthias Welwarsky <matthias@welwarsky.de>

README

@@ -117,17 +117,18 @@ Debug targets
 -------------
 
 ARM11, ARM7, ARM9, AVR32, Cortex-A, Cortex-R, Cortex-M, LS102x-SAP,
-Feroceon/Dragonite, DSP563xx, DSP5680xx, FA526, MIPS EJTAG, NDS32,
-XScale, Intel Quark.
+Feroceon/Dragonite, DSP563xx, DSP5680xx, EnSilica eSi-RISC, FA526, MIPS
+EJTAG, NDS32, XScale, Intel Quark.
 
 Flash drivers
 -------------
 
-ADUC702x, AT91SAM, ATH79, AVR, CFI, DSP5680xx, EFM32, EM357, FM3, FM4, Kinetis,
-LPC8xx/LPC1xxx/LPC2xxx/LPC541xx, LPC2900, LPCSPIFI, Marvell QSPI,
-Milandr, NIIET, NuMicro, PIC32mx, PSoC4, PSoC5LP, SiM3x, Stellaris, STM32,
-STMSMI, STR7x, STR9x, nRF51; NAND controllers of AT91SAM9, LPC3180, LPC32xx,
-i.MX31, MXC, NUC910, Orion/Kirkwood, S3C24xx, S3C6400, XMC1xxx, XMC4xxx.
+ADUC702x, AT91SAM, ATH79, AVR, CFI, DSP5680xx, EFM32, EM357, eSi-TSMC,
+FM3, FM4, Kinetis, LPC8xx/LPC1xxx/LPC2xxx/LPC541xx, LPC2900, LPCSPIFI,
+Marvell QSPI, Milandr, NIIET, NuMicro, PIC32mx, PSoC4, PSoC5LP, SiM3x,
+Stellaris, STM32, STMSMI, STR7x, STR9x, nRF51; NAND controllers of
+AT91SAM9, LPC3180, LPC32xx, i.MX31, MXC, NUC910, Orion/Kirkwood,
+S3C24xx, S3C6400, XMC1xxx, XMC4xxx.
 
 
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