PCI: add pci_try_set_mwi

As suggested by Andrew, add pci_try_set_mwi(), which does not require
return-value checking.

- add pci_try_set_mwi() without __must_check
- make it return 0 on success, errno if the "try" failed or error
- review callers

Signed-off-by: Randy Dunlap <[email protected]>
Cc: Alan Cox <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

11 files changed