libmount: fix mount.nfs segfault, rely on assert() rather than on nonnull

We use
   mnt_optstr_append_option(&o, mnt_fs_get_vfs_options(fs), NULL);

in mount.nfs, unfortunately mnt_optstr_append_option() has been marked
ass nonnull(1, 2). That's wrong because append and prepend should
robust enough to accept NULL as option name.

The patch also removes almost all __attribute__((nonnull). It seems
better to rely on assert() to have usable feedback. In many cases
(nonnull) is premature optimization for the library. This attribute
makes sense for things like strlen() or so...

Addresses: https://bugzilla.redhat.com/show_bug.cgi?id=948274
Signed-off-by: Karel Zak <kzak@redhat.com>
tests: use udevadm settle rather than sleep

Signed-off-by: Karel Zak <kzak@redhat.com>
libmount: add debug message to guess FS function

Signed-off-by: Karel Zak <kzak@redhat.com>
tests: consolidate scsi_debug usage

Signed-off-by: Karel Zak <kzak@redhat.com>
libblkid: arch independent minix detection

It seems that on-disk MINIX FS superblock is native-endian.

Addresses: https://bugzilla.redhat.com/show_bug.cgi?id=833841
Signed-off-by: Karel Zak <kzak@redhat.com>
tests: add BE minix test

Signed-off-by: Karel Zak <kzak@redhat.com>
libblkid: fix silicon raid checksum code on BE

Signed-off-by: Karel Zak <kzak@redhat.com>
libblkid: use more robust code in silicon_raid checksum prober

Signed-off-by: Karel Zak <kzak@redhat.com>
lscpu: set 32-bit / 64-bit for ppc

Signed-off-by: Karel Zak <kzak@redhat.com>
include: fix SYS_{unshare,nsenter} usage

Signed-off-by: Karel Zak <kzak@redhat.com>
build-sys: fix nsenter requirements

Signed-off-by: Karel Zak <kzak@redhat.com>
sulogin: fix compiler warnings

Signed-off-by: Karel Zak <kzak@redhat.com>
fdisks: fix compiler warning

Signed-off-by: Karel Zak <kzak@redhat.com>
build-sys: fix UL_REQUIRES_HAVE

Signed-off-by: Karel Zak <kzak@redhat.com>
build-sys: use pkg-config results for libuser

Our code depends on libuser >= 0.58, it's better to completely rely on
pkg-config results rather than also call UL_CHECK_LIB (that overwrites
previous pkg-config have_user= result independently on libuser
version).

Signed-off-by: Karel Zak <kzak@redhat.com>
tests: fix compiler warning

Signed-off-by: Karel Zak <kzak@redhat.com>
libblkid: make swap detection arch independent

Signed-off-by: Karel Zak <kzak@redhat.com>
libblkid: ubifs is LE

Signed-off-by: Karel Zak <kzak@redhat.com>
libblkid: remove obsolete code

 ... forgot in the previous commit to the swap prober.

Signed-off-by: Karel Zak <kzak@redhat.com>
libfdisk: (gpt) use le64_to_cpu() for alternative LBA checks

Signed-off-by: Karel Zak <kzak@redhat.com>