package/uclibc: fix termios redefinition issue for PowerPC

package/uclibc: fix termios redefinition issue for PowerPC

Fix redefinition of 'struct termios' by syncing termios powerpc headers
from glibc, the commit which fixed the same issue in glibc:

    d4795e4a43e6f0c221bc5dc64c612206a21a177b PowerPC: Fix termios definitions

    https://sourceware.org/git/?p=glibc.git;a=commit;h=d4795e4a43e6f0c221bc5dc64c612206a21a177b

it fixed the following bug request:

    https://bugzilla.redhat.com/show_bug.cgi?id=1122714

In case of Buildroot it fixes flashrom build for PowerPC.

Fixes:
	http://autobuild.buildroot.net/results/797dde5cbf0e94162c7cc7b557841605c78ac2f3/

Signed-off-by: Vadim Kochan <vadim4j@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>