configure: Fix the _BSD_SOURCE define for the Haiku build

The Haiku VM that we are going to add is using _BSD_SOURCE instead
of BSD_SOURCE (without initial underscore)... according to David
Carlier, the BSD_SOURCE without underscore was likely a typo, so
let's simply add the underscore there now.
This fixes the build failure with the bswapXX() macros not being
defined after including <endian.h>.

Message-Id: <20201114165137.15379-2-thuth@redhat.com>
Reviewed-by: Stefan Berger <stefanb@linux.ibm.com
Signed-off-by: Thomas Huth <thuth@redhat.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/configure b/configure
index 4cef321d9d..a273a93377 100755
--- a/configure
+++ b/configure
@@ -790,7 +790,7 @@ SunOS)
 ;;
 Haiku)
   haiku="yes"
-  QEMU_CFLAGS="-DB_USE_POSITIVE_POSIX_ERRORS -DBSD_SOURCE $QEMU_CFLAGS"
+  QEMU_CFLAGS="-DB_USE_POSITIVE_POSIX_ERRORS -D_BSD_SOURCE $QEMU_CFLAGS"
 ;;
 Linux)
   audio_drv_list="try-pa oss"