Correctly return ERANGE in getxattr(2)

According to the getxattr(2) man page the ERANGE errno should be
returned when the size of the value buffer is to small to hold the
result.  Prior to this patch the implementation would just truncate
the value to size bytes.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #1408
Fix various generic kmod RPM spec issues.

There are a number of issues with the generic kmod RPM spec in its
current state:
 - The "%{__id_u}" macro seems to not be available on some systems (e.g.
   Debian squeeze). It appears it has been deprecated. Use "${__id} -u"
   instead.
 - The way the "--with-linux=" configure option is generated in the
   non-RHEL/Fedora case is completely wrong with various newline and
   escaping issues (also, $kernel_version is not available in the
   generator context).

The second issue made the generator shell snippet (almost) silently
fail, which under specific circumstances can result in broken builds
against the wrong kernel sources.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #1416
Possibility to disable (not start) zfs at bootup.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1402
Support .nogitrelease file

When building a custom release in a git tree provide the ability
to prevent the release field from being overwritten by the
`git describe` output.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1402
Add --bump=0 to alien

Preserve the release field when creating Debian packages.  The
--keep-version option was not used because it results in a failure
when the git '<commit>_<hash>' syntax is used for the release.
The '_' is a valid character for RPM packages but not for DEBs.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Turbo Fredriksson <turbo@bayour.com>
Issue #1402
Issue #928
Set RPM_DEFINE_COMMON options

When the kmod packaging was introduced the ability to pass the
--enable-debug and --enable-dmu-tx options from configure all
the way through to `make rpm|deb` was accidenally lost.  Update
ZFS_AC_RPM to explicitlu set RPM_DEFINE_COMMON with these
rpmbuild defines.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Issue #1402
Ignore *.{deb,rpm,tar.gz} files in the top directory.

These are build products and should be ignored.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Turbo Fredriksson <turbo@bayour.com>
Issue #1402