Linux 5.4, in commit (7ce2e76a0420801fb4b53b9e685094 "PCI: Move ASPM
declarations to linux/pci.h") [1], removed pci-aspm.h.
This commit removes the global include of pci-aspm.h in include/dahdi/kernel.h
(because it only pertains to certain drivers), and moves the conditional include
into only the drivers that need it.
[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=7ce2e76a0420801fb4b53b9e685094
Signed-off-by: Shaun Ruffell <sruffell@sruffell.net>