libblkid: Fix marginal C code in probe_lvm2()

Modern gcc accepted what was there previously, but it's clearly not
correct C code, and this may have been the explanation for why a user
trying to compile a recent version of e2fsprogs failed to do so on Red
Hat 7.3.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
1 file changed