imx8mp: issues getting dtb with pcie enabled to boot

[Sahaj Sarup]

Hi,
I am working on the imxmp-verdin platform. One of the quirks with
this particular som is that it uses an internal pcie_phy clock instead of
an external one like most imx8mp boards do.
To get this working on mainline linux, the way clocks are defined for the
pcie_phy is
`clocks = <&hsio_blk_ctrl>;`
However this causes u-boot to completely fail to boot with this
error `Device tree error at node '__symbols__'` .

My end goal is to boot a generic arm image over pcie nvme, I don't know if
this would be possible but atleast a compatible device tree would be a good
starting point.

Thanks.