Bug 2745

Problem Description
======================
augeas build failed. augeas depends on the libxml2 when configing,
but augeas bb file doesn't specify this depending, so
sometimes augeas build failed.



Expected Behavior
======================
augeas should build successfully!


Observed Behavior
======================
| checking for MAP_ANONYMOUS... yes
| checking for mmap... (cached) yes
| checking for MAP_ANONYMOUS... yes
| checking whether symlink handles trailing slash correctly... guessing no
| checking for pthread_atfork... yes
| checking for unsetenv... yes
| checking for unsetenv() return type... int
| checking whether unsetenv obeys POSIX... guessing no
| checking for a traditional french locale... (cached) fr_FR
| checking for a french Unicode locale... (cached) none
| checking for a traditional japanese locale... (cached) none
| checking for a transitional chinese locale... (cached) none
| checking whether wctob works... (cached) yes
| checking whether wctob is declared... (cached) yes
| checking for sched_yield in -lrt... yes
| checking for x86_64-wrs-linux-pkg-config... no
| checking for pkg-config... /build/Build/fli/my_build/x86-64-kvm-guest/bitbake_build/tmp/sysroots/i686-linux/usr/bin/pkg-config
| checking pkg-config is at least version 0.9.0... yes
| checking for LIBXML... no
| configure: error: Package requirements (libxml-2.0) were not met:
|
| No package 'libxml-2.0' found
|
| Consider adjusting the PKG_CONFIG_PATH environment variable if you
| installed software in a non-standard prefix.
|
| Alternatively, you may set the environment variables LIBXML_CFLAGS
| and LIBXML_LIBS to avoid the need to call pkg-config.
| See the pkg-config man page for more details.
| ERROR: oe_runconf failed
| ERROR: Function failed: do_configure (see /build/Build/fli/my_build/x86-64-kvm-guest/bitbake_build/tmp/work/x86_64-wrs-linux/augeas-0.10.0-r1/temp/do_configure/log.do_configure.5632 for further information)
NOTE: package augeas-0.10.0-r1: task do_configure: Failed
ERROR: Task 6 (/build/Build/fli/my_build/x86-64-kvm-guest/layers/oe-core/meta/recipes-extended/augeas/augeas_0.10.0.bb, do_configure) failed with exit code '1'
NOTE: Tasks Summary: Attempted 425 tasks of which 421 didn't need to be rerun and 1 failed.

Summary: 1 task failed:
  /build/Build/fli/my_build/x86-64-kvm-guest/layers/oe-core/meta/recipes-extended/augeas/augeas_0.10.0.bb, do_configure
Summary: There was 1 ERROR message shown, returning a non-zero exit code.
make: *** [augeas] Error 1
make: Leaving directory `/build/Build/fli/my_build/x86-64-kvm-guest/build'



Steps to Reproduce
======================
configure --enable-board=intel-atom --enable-rootfs=glibc_std --enable-kernel=standard --with-layer=<wrll-runtime-testing>/userspace
 --with-template=feature/userspace-base

make fs

make -C build augeas.distclean
make -C build libxml2.distclean
make -C build augeas