[meta-xilinx] Build and boot zcu106 image

[Mike Looijmans]

Got a zcu106 board here to experiment with. With pre-built stuff, the board 
boots okay.

I cloned OpenEmbedded and meta-xilinx "thud" branches, made no changes.

Built the PMU firmware and core-image-minimal for machine zcu106-zynqmp.

Copied the usual files onto an SD card: atf-uboot.ub boot.bin Image system.dtb 
u-boot.bin uEnv.txt zynqmp-zcu106-revA.dtb

Put the card in the board and switch it on. All I get is this:

<debug_uart> Debug uart enabled
"Synchronous Abort" handler, esr 0x96000040
ELR:     fffc9e70
LR:      fffc6c78
x0 : fdfd00011dfdfe5d x1 : 0000000000000000
x2 : 0202ffff020201a3 x3 : fdfd00011dfdfe5d
x4 : 0000000000000000 x5 : 0000000000000000
x6 : 00000000ffff7f20 x7 : 0000000000000005
x8 : 00000000000000ad x9 : 0000000000000080
x10: 000000000000fffd x11: 0000000000000064
x12: 00000000fffffe6a x13: 60f8a90300b080a0
x14: 8a10070a42650000 x15: a5cc22ca484081d9
x16: 385a360321460003 x17: 9b800c890e560844
x18: 00000000ffff7e90 x19: 0000000020000000
x20: 0000000000000000 x21: fdfd00011dfdfe5d
x22: 0000000000000000 x23: 0000000000000001
x24: 00000000ffff7f20 x25: 00000000fffdae68
x26: 00000000fffdae68 x27: 00000000fffdb000
x28: 0000000000000000 x29: 00000000ffff7c10

Resetting CPU ...

### ERROR ### Please RESET the board ###


What does one have to do to actually boot that board with meta-xilinx?