libblkid: befs: declare functions static

libblkid: befs: declare functions static

Since commit 0b0c231f64d02e682
(swapon: move generic code to swapon-common.c), if util-linux is
configured with --enable-static --disable-shared --enable-libmount-mount
options, the build fails with the following error:

  ...
  libtool: link: gcc -std=gnu99 -fsigned-char -ggdb -O1 -Wall -D_FORTIFY_SOURCE=2 -o switch_root switch_root.o
  /home/petr/upstream/util-linux/libblkid/src/.libs/libblkid.a(befs.o): In function `get_uuid':
  /home/petr/upstream/util-linux/libblkid/src/superblocks/befs.c:333: multiple definition of `get_uuid'
  swapon-swapon-common.o:/home/petr/upstream/util-linux/sys-utils/swapon-common.c:99: first defined here
  collect2: ld returned 1 exit status
  /bin/sh ../libtool  --tag=CC   --mode=link gcc -std=gnu99 -fsigned-char -ggdb -O1 -Wall -D_FORTIFY_SOURCE=2   -o flock flock.o strutils.o
  libtool: link: gcc -std=gnu99 -fsigned-char -ggdb -O1 -Wall -D_FORTIFY_SOURCE=2 -o pivot_root pivot_root.o
  make[2]: *** [swapon] Error 1
  make[2]: *** Waiting for unfinished jobs....
  /home/petr/upstream/util-linux/libblkid/src/.libs/libblkid.a(befs.o): In function `get_uuid':
  /home/petr/upstream/util-linux/libblkid/src/superblocks/befs.c:333: multiple definition of `get_uuid'
  swapoff-swapon-common.o:/home/petr/upstream/util-linux/sys-utils/swapon-common.c:99: first defined here

Fix by declaring befs funcitons static.

Signed-off-by: Petr Uzel <petr.uzel@suse.cz>