ARC: Update docs

It seems pkg-config must be installed starting from Ubuntu 14.04.

Signed-off-by: Anton Kolesov <Anton.Kolesov@synopsys.com>
ARC: Add configuration files for DW ARC AXS101

Add configuration files for the DesignWare ARC AXS101 Software Development
Platform:

1. Definition of the JTAG interface embedded into the mainboard.
2. Definition of the AXC001 CPU card.
3. Definition of the mainboard.

Signed-off-by: Anton Kolesov <Anton.Kolesov@synopsys.com>
ARC: Add new configurations for EM Starter Kit

Use same board/target hierarchy as in SDP.

Signed-off-by: Anton Kolesov <Anton.Kolesov@synopsys.com>
ARC: Update README

Signed-off-by: Anton Kolesov <Anton.Kolesov@synopsys.com>
ARC: Add configuration files for DW ARC AXS102

Board with HS34 and HS36.

Signed-off-by: Anton Kolesov <Anton.Kolesov@synopsys.com>