random: ctr_drbg: Fix sys_csrand_get types

This implementation of sys_csrand_get was using a
different type for the length parameter.

Signed-off-by: Flavio Ceolin <flavio@hubblenetwork.com>

subsys/random/random_ctr_drbg.c

@@ -62,7 +62,7 @@ static int ctr_drbg_initialize(void)
 }
 
 
-int z_impl_sys_csrand_get(void *dst, uint32_t outlen)
+int z_impl_sys_csrand_get(void *dst, size_t outlen)
 {
 	int ret;