linux: Host PCIe VGA and random number fixes

Joel Stanley (2):
      ARM: dts: aspeed: Describe random number device
      clk: aspeed: Mark bclk (PCIe) and dclk (VGA) as critical

Fixes: openbmc/openbmc#2978
Tested: Booted image on Romulus and observed VGA output
Change-Id: I65c665cd3e4bae5b5e3ee5cd7607cb9b71021e6f
Signed-off-by: Joel Stanley <joel@jms.id.au>