libc/uClibc: portability fixes to install_headers

Add patch files for uClibc-0.9.30:
extra/scripts/install_headers.sh: find must be called with path.
extra/scripts/unifdef.c: getline is declared in <stdio.h>, use different name.

Reported-by: "Guylhem Aznar" <crossgcc@guylhem.net>
Reported-by: "Titus von Boxberg" <titus@v9g.de>
Signed-off-by: "Titus von Boxberg" <titus@v9g.de>
(transplanted from b745004e1d29921a86b73694d912f1e1277db3e1)

reporter_name="Bart vdr. Meulen <bartvdrmeulen@gmail.com>"

reporter_url=""

reporter_comment="Config to build cross-compiler with mingw as kernel type"