iut: Enable IPM build in prj.conf

This change makes IUT FW have IPM driver build. Then CI can capture any IPM
build failure.

Signed-off-by: Dong Wang <dong.d.wang@intel.com>

Author: kwd-doodling

zephyr/iut_test/prj.conf

@@ -45,6 +45,9 @@ CONFIG_GPIO=y
 # SPI
 CONFIG_SPI=y
 
+# IPC/IPM
+CONFIG_IPM=y
+
 CONFIG_PM=y
 CONFIG_SHELL_BACKEND_SERIAL_INTERRUPT_DRIVEN=n
 CONFIG_SHELL_BACKEND_SERIAL_RX_POLL_PERIOD=1