gdb/solib-rocm: remove one xfree

Replace a manual xfree with unique_xmalloc_ptr.

Change-Id: I12a20106545905f1a80d069fc0555812cc3d6680
Approved-By: Tom Tromey <tom@tromey.com>
Approved-by: Lancelot Six <lancelot.six@amd.com> (amdgpu)
1 file changed