riscv: Increase TEST_EXTRA_STACK_SIZE to 4096 if c++ exceptions

Initializing the C++ stack unwinding data structures takes quite a bit
of stack space. Increase the TEST_EXTRA_STACK_SIZE when using these.

Signed-off-by: Keith Packard <[email protected]>

Author: keith-packard

arch/riscv/Kconfig

@@ -428,6 +428,7 @@ config MAIN_STACK_SIZE
 	default 2048 if PMP_STACK_GUARD
 
 config TEST_EXTRA_STACK_SIZE
+	default 4096 if CPP_EXCEPTIONS
 	default 1536
 
 config CMSIS_THREAD_MAX_STACK_SIZE