ARM: dts: socfpga: removal of generic PE1 dts

ARM: dts: socfpga: removal of generic PE1 dts

Remove the older socfpga_arria10_mercury_pe1.dts, since it is duplicate,
the hardware is covered by the combination of Enclustra's .dtsi files.

The older .dts was limited to only the case of having an Enclustra
Mercury+ AA1 on a Mercury+ PE1 base board, booting from sdmmc. This
functionality is provided also by the generic Enclustra dtsi and dts
files, in particular socfpga_arria10_mercury_aa1_pe1_sdmmc.dts. Since
both .dts files cover the same, the older one is to e replaced in
favor of the more modularized approach.

Signed-off-by: Lothar Rubusch <l.rubusch@gmail.com>
Acked-by: Steffen Trumtrar <s.trumtrar@pengutronix.de>
Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>