t104xrdb: Add Errata A_007662, A_008007 workaround in pbi.cfg

-A_007662 states that for x1 link width, PCIe2 controller trains in
 Gen1 speed while configured for Gen2 speed.
 Workaround:Set the width to x1 and speed to Gen2 by writing to
 CCSR registers in PBI phase

-A_008007 states that PVR register may show random value.
 Workaround: Reset PVR register using DCSR space in PBI phase

Add PBI based software workaround for A_007662 and A_008007
in t104x_pbi.cfg. This is required for SPL-based bootloaders
like NAND-boot, SD-boot, SPI-boot

Signed-off-by: Priyanka Jain <Priyanka.Jain@freescale.com>
Reviewed-by: York Sun <yorksun@freescale.com>