qspi: t210: Fix claim_bus's use of the wrong bus/device
claim_bus() is passed a udevice *dev, which is the bus device's parent.
In this driver, claim_bus assumed it was the bus, which caused the
'priv' info pointer to be wrong, and periph_id was incorrect. This in
turn caused the periph clock call to assign the wrong clock (PLLM
instead of PLLP0), which caused a kernel warning. I only saw the 'bad'
periph_id when enabling DEBUG due to an assert. Not sure how QSPI was
working w/this errant clock, but it was moot as QSPI wasn't active
unless you probed it, and that wasn't happening until I posted a patch
to enable env save to QSPI for Nano (coming soon).