librsvg: disable Bsymbolic if it is not supported on some hosts

When trying to build on my Centos 5.5 machine, got below error:
| checking for gdk-pixbuf-query-loaders... /home/build/clu1/build/qemux86_standard_glibc-std/bitbake_build/tmp/sysroots/x86_64-linux/usr/bin/gdk-pixbuf-query-loaders
| checking if gcc  supports "-Wl,-Bsymbolic-functions" flag...
| configure: error: -Bsymbolic requested but not supported by ld. Use --disable-Bsymbolic to disable
| Configure failed. The contents of all config.log files follows to aid debugging
| ERROR: oe_runconf failed

Set --enable-Bsymbolic=auto to disable it when it is not suppported.

Signed-off-by: Chong Lu <Chong.Lu@windriver.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
buildhistory: rename build-id to build-id.txt and add more info

* use .txt extension like other reports (e.g. image-info.txt) it's
  also useful when looking at the file from web server which doesn't
  have text/plain as default content-type
* include whole BUILDCFG_HEADER/BUILDCFG_FUNCS instead of just layer
  info
* this makes it easier for distro to include more fields without the
  need to modify buildhistory.bbclass
* currently it adds following fields:
  Build Configuration:
  BB_VERSION        = "1.23.1"
  BUILD_SYS         = "x86_64-linux"
  NATIVELSBSTRING   = "Gentoo-2.2"
  TARGET_SYS        = "x86_64-oe-linux"
  MACHINE           = "qemux86-64"
  DISTRO            = "shr"
  DISTRO_VERSION    = "2013.07-next-20140725"
  TUNE_FEATURES     = "m64 core2"
  TARGET_FPU        = ""

Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
classes/sstate: ensure do_package_qa_setscene doesn't pull in do_package_setscene

If we have done do_package_qa_setscene we do not also need
do_package_setscene. This means we can again for example rebuild an image
without needing do_package sstate packages to be present.

Signed-off-by: Paul Eggleton <paul.eggleton@linux.intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
qemu: fix Darwin cross-compilation

Darwin target will not be detected correctly
if qemu is cross-compiled under a Linux host.

Signed-off-by: Cristian Iorga <cristian.iorga@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>