rpi-userland: cleanup *_CONF_OPT

This change reverts the commit 5e3b1f31b3f82e3b163567f10d7131c9d649a2cf
because rpi-userland is correctly built whatever the value of the
BUILD_SHARED_LIBS CMake flags.

The cset 5e3b1f31b3f82e3b163567f10d7131c9d649a2cf originally intends to
fix linkage/runtime failure in xbmc package because of missing flags in
xbmc LIBS env. var. This has been fixed in the previous patch.

So, for rpi-userland package, BUILD_SHARED_LIBS does no longer need to
be forced to OFF, and can safely be driven by the CMake infrastructure.

Signed-off-by: Samuel Martin <s.martin49@gmail.com>
Cc: "Yann E. MORIN" <yann.morin.1998@free.fr>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Tested-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Acked-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Tested-by: "Maxime Hadjinlian" <maxime.hadjinlian@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/rpi-userland/rpi-userland.mk

@@ -9,7 +9,7 @@ RPI_USERLAND_SITE = $(call github,raspberrypi,userland,$(RPI_USERLAND_VERSION))
 RPI_USERLAND_LICENSE = BSD-3c
 RPI_USERLAND_LICENSE_FILES = LICENCE
 RPI_USERLAND_INSTALL_STAGING = YES
-RPI_USERLAND_CONF_OPT = -DVMCS_INSTALL_PREFIX=/usr -DBUILD_SHARED_LIBS=OFF
+RPI_USERLAND_CONF_OPT = -DVMCS_INSTALL_PREFIX=/usr
 
 RPI_USERLAND_PROVIDES = libegl libgles libopenmax libopenvg