Add missing depends in x509 programs
diff --git a/programs/x509/cert_req.c b/programs/x509/cert_req.c
index 8a545a4..01b8107 100644
--- a/programs/x509/cert_req.c
+++ b/programs/x509/cert_req.c
@@ -34,12 +34,12 @@
 #endif
 
 #if !defined(POLARSSL_X509_CSR_WRITE_C) || !defined(POLARSSL_FS_IO) ||  \
-    !defined(POLARSSL_PK_PARSE_C) ||                                    \
+    !defined(POLARSSL_PK_PARSE_C) || !defined(POLARSSL_SHA256_C) || \
     !defined(POLARSSL_ENTROPY_C) || !defined(POLARSSL_CTR_DRBG_C)
 int main( void )
 {
     polarssl_printf( "POLARSSL_X509_CSR_WRITE_C and/or POLARSSL_FS_IO and/or "
-            "POLARSSL_PK_PARSE_C and/or "
+            "POLARSSL_PK_PARSE_C and/or POLARSSL_SHA256_c and/or "
             "POLARSSL_ENTROPY_C and/or POLARSSL_CTR_DRBG_C "
             "not defined.\n");
     return( 0 );