We had a distributed file (remote_protocol.h, which in turn was
a prereq to remote_driver.c) depending on a generated file
(libvirt_probes.h), which is a no-no for a VPATH build from a
read-only source tree (no wonder 'make distcheck' tests precisely
that situation):

     File `libvirt_driver_remote.la' does not exist.
       File `libvirt_driver_remote_la-remote_driver.lo' does not exist.
             Prerequisite `libvirt_probes.h' is newer than target `../../src/remote/remote_protocol.h'.
            Must remake target `../../src/remote/remote_protocol.h'.
Invoking recipe from Makefile:7464 to update target `../../src/remote/remote_protocol.h'.
make[3]: Entering directory `/home/remote/eblake/libvirt-tmp2/build/libvirt-0.9.12/_build/src'
  GEN    ../../src/remote/remote_protocol.h
cannot create ../../src/remote/remote_protocol.h: Permission denied at ../../src/rpc/genprotocol.pl line 31.
make[3]: *** [../../src/remote/remote_protocol.h] Error 13

Rather than making distributed .c files depend on generated files, we
really want to ensure that compilation into .lo files is not attempted
until the generated files are present, done by this patch.  Since there
were two different sets of conditionally generated files that both
feed the .lo file, I had to introduce a new variable REMOTE_DRIVER_PREREQS
to keep automake happy.

After that fix, the next issue was that make treats './foo' and 'foo'
differently in determining whether an implicit %foo rule is applicable,
with the result that locking/qemu-sanlock.conf wasn't properly being
built at the right times.  Also, the output for using the .aug test
files was a bit verbose.

After fixing the src directory, the next error is related to the docs
directory, where the tarball is missing a stamp file and thus tries to
regenerate files that are already present:

  GEN    ../../docs/apibuild.py.stamp
Traceback (most recent call last):
  File "../../docs/apibuild.py", line 2511, in <module>
    rebuild("libvirt")
  File "../../docs/apibuild.py", line 2495, in rebuild
    builder.serialize()
  File "../../docs/apibuild.py", line 2424, in serialize
    output = open(filename, "w")
IOError: [Errno 13] Permission denied: '../../docs/libvirt-api.xml'
make[5]: *** [../../docs/apibuild.py.stamp] Error 1

and fixing that exposed another case of a distributed file (generated
html) depending on a built file (libvirt.h), but only when doing an
in-tree build, because of a file glob.

* src/Makefile.am ($(srcdir)/remote/remote_driver.c): Change...
(libvirt_driver_remote_la-remote_driver.lo): ...to the real
dependency.
($(builddir)/locking/%-sanlock.conf): Drop $(builddir), so that
rule gets run in time for test_libvirt_sanlock.aug.
(test_libvir*.aug): Cater to silent build.
(conf_DATA): Don't ship qemu-sanlock.conf in the tarball, since it
is trivial to regenerate.
* docs/Makefile.am (EXTRA_DIST): Ship our stamp file.
($(APIBUILD_STAMP)): Don't depend on generated file.