Add precision about exploitability in ChangeLog

Also fix some whitespace while at it.

ChangeLog

@@ -5,6 +5,7 @@ mbed TLS ChangeLog (Sorted per branch, date)
 Security
    * Fix potential integer overflow to buffer overflow in
      mbedtls_rsa_rsaes_pkcs1_v15_encrypt and mbedtls_rsa_rsaes_oaep_encrypt
+     (not triggerable remotely in (D)TLS).
 
 Bugfix
    * Fix bug in mbedtls_mpi_add_mpi() that caused wrong results when the three

library/rsa.c

@@ -595,7 +595,7 @@ int mbedtls_rsa_rsaes_pkcs1_v15_encrypt( mbedtls_rsa_context *ctx,
         return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );
 
     olen = ctx->len;
-    
+
     // first comparison checks for overflow
     if( ilen + 11 < ilen || olen < ilen + 11 )
         return( MBEDTLS_ERR_RSA_BAD_INPUT_DATA );