staging: mt7621-pci: make cleaner 'mt7621_pcie_enable_ports'

staging: mt7621-pci: make cleaner 'mt7621_pcie_enable_ports'

Function 'mt7621_pcie_enable_ports' call 'mt7621_pcie_enable_port'
for each available pcie port. Instead of having two for loops
there just move needed initialization. There is one setting
that can be removed which is the set for 'PCI_COMMAND_MASTER'
bit. Pci drivers are in charge of set that bit if is really
needed and should be not a mission of the controller to do that.

Signed-off-by: Sergio Paracuellos <sergio.paracuellos@gmail.com>
Link: https://lore.kernel.org/r/20210607120153.24989-2-sergio.paracuellos@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>