ARM: mmp: remove tavorevb board support

ARM: mmp: remove tavorevb board support

There are two tavorevb boards in the kernel, one using a PXA930 chip in
mach-pxa, and one using the later PXA910 chip in mach-mmp.  They use the
same board number, which is generally a bad idea, and in a multiplatform
kernel, we can end up with funny link errors like this one resulting
from two boards gettting controlled by the same Kconfig symbol:

arch/arm/mach-mmp/tavorevb.o: In function `tavorevb_init':
tavorevb.c:(.init.text+0x4c): undefined reference to `pxa910_device_uart1'
tavorevb.c:(.init.text+0x50): undefined reference to `pxa910_device_gpio'
tavorevb.o:(.arch.info.init+0x54): undefined reference to `pxa910_init_irq'
tavorevb.o:(.arch.info.init+0x58): undefined reference to `pxa910_timer_init'

The mach-pxa TavorEVB seems much more complete than the mach-mmp one
that supports only uart, gpio and ethernet. Further, I could find no
information about the board on the internet aside from references to
the Linux kernel, so I assume this was never available outside of Marvell
and can be removed entirely.

There is a third board named TavorEVB in the Kconfig description,
but this refers to the "TTC_DKB" machine. The two are clearly
related, so I change the Kconfig description to just list both
names.

Cc: Lubomir Rintel <lkundrak@v3.sk>
Reviewed-by: Lubomir Rintel <lkundrak@v3.sk>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>