package/libiscsi: do not built the manpages

The pre-rendered, bundled ones are still installed, though, but they
get removed in target-finalize anyway.

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
(cherry picked from commit 5b5c84a2a82407f7728d53ac79f0fde59f677fc3)
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/libiscsi/libiscsi.mk

@@ -11,7 +11,7 @@ LIBISCSI_LICENSE_FILES = COPYING LICENCE-GPL-2.txt LICENCE-LGPL-2.1.txt
 LIBISCSI_INSTALL_STAGING = YES
 LIBISCSI_AUTORECONF = YES
 
-LIBISCSI_CONF_OPTS = --disable-werror
+LIBISCSI_CONF_OPTS = --disable-werror --disable-manpages
 
 # We need to create the m4 directory to make autoreconf work properly.
 define LIBISCSI_CREATE_M4_DIR