iwlwifi: remove dump_regs() from transport ops

This is used only within PCIe, and there's no reason to go through
the transport methods for a function call within PCIe itself.
Remove the dump_regs() method and call the function directly.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>