Remove regformats/tic6x-{c62x,c64x,c64xp}.dat

tic6x-uclinux GDBserver uses linux target descriptions, instead of these
non-linux target descriptions.  So we can remove these *.dat files.

gdb:

2017-10-16  Yao Qi  <yao.qi@linaro.org>

	* features/Makefile (WHICH): Remove tic6x-c64xp, tic6x-c64x
	tic6x-c62x.
	* regformats/tic6x-c62x.dat: Remove.
	* regformats/tic6x-c64x.dat: Remove.
	* regformats/tic6x-c64xp.dat: Remove.
5 files changed