encore: set REVERSE_Y_FLAG for ft5x06 touchscreen

The driver currently behaves as if this flag is set regardless of the
actual value of the flags (really, BN?).  Let's actually set this flag
so that the value of flags matches the behavior.
ft5x06: don't assume REVERSE_Y_FLAG is set

After all, what's the point of having such a flag if you ignore its
value?
cyttsp: add support for flipping and reversing coordinate axes

This is needed to support touchscreen installations which don't match
the "natural" orientation of the device.
encore: add support for changing default screen orientation

We need this if we don't want to use rotation in SurfaceFlinger (buggy
in CM10.1).
encore_cm10.1_defconfig: set CONFIG_ENCORE_ORIENTATION_LANDSCAPE

This allows us to avoid using the buggy ro.sf.hwrotation feature of
SurfaceFlinger.