package/jailhouse: install files to /usr

The jailhouse package installs files in the /usr/local prefix. This is
not convenient, because the jailhouse binary ends up in /usr/local/sbin,
which is not in the default Buildroot PATH. See [1]. Moreover, all
other Buildroot packages install files in /usr.

This is because the Buildroot package recipe does not set any prefix
value, and the upstream Jailhouse Makefile has a default to /usr/local.
See [2].

This commit sets the prefix value in the JAILHOUSE_MAKE_OPTS and also
updates other installation commands to put all the files in /usr.

[1] https://gitlab.com/buildroot.org/buildroot/-/blob/2023.11.1/system/Config.in#L495
[2] https://github.com/siemens/jailhouse/blob/v0.12/scripts/include.mk#L22

Signed-off-by: Julien Olivain <ju.o@free.fr>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>

package/jailhouse/jailhouse.mk

@@ -15,7 +15,8 @@ JAILHOUSE_MAKE_OPTS = \
 	CROSS_COMPILE="$(TARGET_CROSS)" \
 	ARCH="$(KERNEL_ARCH)" \
 	KDIR="$(LINUX_DIR)" \
-	DESTDIR="$(TARGET_DIR)"
+	DESTDIR="$(TARGET_DIR)" \
+	prefix=/usr
 
 ifeq ($(BR2_PACKAGE_JAILHOUSE_HELPER_SCRIPTS),y)
 JAILHOUSE_DEPENDENCIES += \
@@ -60,8 +61,8 @@ define JAILHOUSE_INSTALL_TARGET_CMDS
 	$(INSTALL) -d -m 0755 $(TARGET_DIR)/etc/jailhouse
 	$(INSTALL) -D -m 0644 $(@D)/configs/*/*.cell $(TARGET_DIR)/etc/jailhouse
 
-	$(INSTALL) -d -m 0755 $(TARGET_DIR)/usr/local/libexec/jailhouse/demos
-	$(INSTALL) -D -m 0755 $(@D)/inmates/demos/*/*.bin $(TARGET_DIR)/usr/local/libexec/jailhouse/demos
+	$(INSTALL) -d -m 0755 $(TARGET_DIR)/usr/libexec/jailhouse/demos
+	$(INSTALL) -D -m 0755 $(@D)/inmates/demos/*/*.bin $(TARGET_DIR)/usr/libexec/jailhouse/demos
 
 	$(JAILHOUSE_INSTALL_HELPER_SCRIPTS)
 endef