elfutils: fix building elfutils-native with GCC7
This is heavily based on the oe-core master commit with the same
subject, but includes a backport of upstream's fix for the fallthrough
warnings rebased to 0.166 (the oe-core patch which targeted 0.168 did
not apply), a rebase of the format-truncation patch, and a backport of
the upstream format-length patch.
Info from OE-Core master patch follows:
From OE-Core rev:
aaf4c4f3d09ac3897205417eb15e19d54e0c0d05
From: Joshua Lock <joshua.g.lock@intel.com>
Backport a fix from upstream for a -Wformat-truncation=2 warning
and implement a simple fix for a -Wimplicit-fallthrough warning.
Signed-off-by: Joshua Lock <joshua.g.lock@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
Signed-off-by: Cody P Schafer <dev@codyps.com>
Signed-off-by: Armin Kuster <akuster808@gmail.com>
