ARM: pxa: remove eseries.h

ARM: pxa: remove eseries.h

Commit e478fe4cd50b86e95fadc415438b63fa94060b7d ("[ARM] pxa: merge all
eseries board code into eseries.c") removed all six files that included
eseries.h. Everything that this header provides is now either local to
eseries.c or entirely unused. It was apparently just an oversight to
keep this header. This header can safely be removed.

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Tested-by: Eric Miao <eric.y.miao@gmail.com>
Signed-off-by: Haojian Zhuang <haojian.zhuang@gmail.com>