package/poppler: autoconf options take two dashes

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Cc: Olivier Schonken <olivier.schonken@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/poppler/poppler.mk

@@ -74,9 +74,9 @@ endif
 
 ifeq ($(BR2_PACKAGE_OPENJPEG),y)
 POPPLER_DEPENDENCIES += openjpeg
-POPPLER_CONF_OPTS += -enable-libopenjpeg=openjpeg1
+POPPLER_CONF_OPTS += --enable-libopenjpeg=openjpeg1
 else
-POPPLER_CONF_OPTS += -enable-libopenjpeg=none
+POPPLER_CONF_OPTS += --enable-libopenjpeg=none
 endif
 
 $(eval $(autotools-package))