Use the correct field f_frsize instead of f_bsize.
The statfs f_bsize is the "Optimal transfer block size" while the
f_frsize is the "Fragment size (since Linux 2.6)". On some FUSE
filesystems those may differ.
Fixes bug 9046
URL: https://bugs.busybox.net/show_bug.cgi?id=9046
Signed-off-by: Natanael Copa <ncopa@alpinelinux.org>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>