boards: qemu_cortex_m3: enable test random generator for BT

BT uses PSA Crypto API to perform crypto operations and, on this
platform, these APIs are implemented through Mbed TLS. In order
to properly initialize this library, a random number generator
is required. Since this platform does not have a true random
number generator, we enable the test one. This holds only
when BT is enabled, of course.

Signed-off-by: Valerio Setti <[email protected]>

Author: valeriosetti

boards/qemu/cortex_m3/Kconfig.defconfig

@@ -12,4 +12,13 @@ choice NULL_POINTER_EXCEPTION_DETECTION
 	default NULL_POINTER_EXCEPTION_DETECTION_NONE
 endchoice
 
+# BT relies on PSA Crypto API to perform crypto operations and, on this platform,
+# these APIs are provided thougth Mbed TLS. Unfortunately this platform is not
+# provided with a true random number generator which is required to properly
+# initialize the PSA Crypto core, so we need to enable the fake TEST_RANDOM_GENERATOR.
+config TEST_RANDOM_GENERATOR
+	bool
+	depends on BT
+	default y
+
 endif # BOARD_QEMU_CORTEX_M3