[dpdk-kmods v2] linux/igb_uio: fix build for switch fall through

[Thomas Monjalon]

16/12/2021 13:03, Ferruh Yigit:
> Linux is using '-Wimplicit-fallthrough=5' compiler option, which doesn't
> take any fall through comments into account but only uses compiler
> 'fallthrough' attribute to document fall through action is intended.
> 
> "falls through" comment was used in the code which is causing a build
> error now, this patch converts comment to the 'fallthrough' macro
> defined in the Linux.
> 
> To cover the case where an old Linux version doesn't have the macro,
> defined it in the compatibility header too.
> 
> Signed-off-by: Ferruh Yigit <ferruh.yigit at intel.com>

Applied, thanks.