[Buildroot] [PATCH v1] qt: fix postgresql plugin configure

[Peter Seiderer]

Add additional -lpthread to fix postgresql plugin configure test.

Fixes [1]:

  PostgreSQL support cannot be enabled due to functionality tests!
   Turn on verbose messaging (-v) to ./configure to see the final report.
   If you believe this message is in error you may use the continue
   switch (-continue) to ./configure to continue.
  make: *** [/home/test/autobuild/instance-1/output/build/qt-4.8.6/.stamp_configured] Error 101
  make: Leaving directory `/home/test/autobuild/instance-1/buildroot'

Verbose configure output:

  PostgreSQL auto-detection... ()
  compiling psql.cpp
  linking psql
  .../host/usr/i686-buildroot-linux-uclibc/sysroot/usr/lib/libcrypto.so.1.0.0: warning: gethostbyname is obsolescent, use getnameinfo() instead.
  .../host/usr/i686-buildroot-linux-uclibc/sysroot/usr/lib/libpq.so: undefined reference to `pthread_sigmask'
  collect2: error: ld returned 1 exit status
  Makefile:99: recipe for target 'psql' failed
  gmake[2]: *** [psql] Error 1
  PostgreSQL disabled.

[1] http://autobuild.buildroot.net/results/8c1/8c1e18a181f355ab8870c5d3d70cf9d757b6f225/

Signed-off-by: Peter Seiderer <ps.report at gmx.net>
---
 package/qt/qt.mk | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/package/qt/qt.mk b/package/qt/qt.mk
index d1615ae..8a762e8 100644
--- a/package/qt/qt.mk
+++ b/package/qt/qt.mk
@@ -348,7 +348,10 @@ QT_CONFIGURE_OPTS += -qt-sql-odbc
 QT_DEPENDENCIES += unixodbc
 endif
 ifeq ($(BR2_PACKAGE_QT_PSQL),y)
-QT_CONFIGURE_OPTS += -qt-sql-psql -psql_config $(STAGING_DIR)/usr/bin/pg_config
+# additional -lpthread needed for uclibc/libpq.so linking configure test
+QT_CONFIGURE_OPTS += -qt-sql-psql \
+	-psql_config $(STAGING_DIR)/usr/bin/pg_config \
+	-lpthread
 QT_DEPENDENCIES += postgresql
 endif
 ifeq ($(BR2_PACKAGE_QT_SQLITE_QT),y)
-- 
2.1.4