Reapply "Update openhd.mk"

This reverts commit 85386af.

external/buildroot/package/openhd/openhd.mk

@@ -28,5 +28,15 @@ OPENHD_CONF_OPTS = -DENABLE_USB_CAMERAS=OFF
 # List of dependencies that must be built before OpenHD
 OPENHD_DEPENDENCIES = libsodium gstreamer1 gst1-plugins-base libpcap host-pkgconf poco
 
+# Define the CMake build commands to correctly set Poco_DIR or CMAKE_PREFIX_PATH
+define OPENHD_BUILD_CMDS
+    $(TARGET_CONFIGURE_OPTS) \
+    cmake -DCMAKE_INSTALL_PREFIX=$(TARGET_DIR) \
+          -DCMAKE_BUILD_TYPE=Release \
+          -DCMAKE_PREFIX_PATH=$(STAGING_DIR)/usr/lib/cmake/Poco \
+          $(OPENHD_CONF_OPTS) \
+          $(@D)
+endef
+
 # Use Buildroot's CMake package infrastructure to handle the build
 $(eval $(cmake-package))