Add missing asterisk to doxygen closures

Clarify section names next to closing braces
Signed-off-by: Andrzej Kurek <andrzej.kurek@arm.com>
diff --git a/include/mbedtls/platform.h b/include/mbedtls/platform.h
index bdef074..0bd633b 100644
--- a/include/mbedtls/platform.h
+++ b/include/mbedtls/platform.h
@@ -127,7 +127,7 @@
 #endif /* MBEDTLS_PLATFORM_NO_STD_FUNCTIONS */
 
 
-/* \} name SECTION: Module settings */
+/** \} name SECTION: Module settings */
 
 /*
  * The function pointers for calloc and free.