Resolve an uninitialized variable warning when compiling.
In function ‘zfs_domount’:
warning: ‘root_inode’ may be used uninitialized in this
function [-Wmaybe-uninitialized]
sb->s_root = d_make_root(root_inode);
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes#11306