Fix multiple quality issues in the source

This PR fixes multiple issues in the source code to address issues raised by
tests/scripts/check-files.py. Specifically:
 * incorrect file permissions
 * missing newline at the end of files
 * trailing whitespace
 * Tabs present
 * TODOs in the souce code
diff --git a/include/mbedtls/rsa.h b/include/mbedtls/rsa.h
index 8e34e62..9dd4e67 100644
--- a/include/mbedtls/rsa.h
+++ b/include/mbedtls/rsa.h
@@ -345,7 +345,7 @@
  *                 as large as the size ctx->len of ctx->N (eg. 128 bytes
  *                 if RSA-1024 is used) to be able to hold an arbitrary
  *                 decrypted message. If it is not large enough to hold
- *                 the decryption of the particular ciphertext provided, 
+ *                 the decryption of the particular ciphertext provided,
  *                 the function will return MBEDTLS_ERR_RSA_OUTPUT_TOO_LARGE.
  *
  * \note           The input buffer must be as large as the size
@@ -377,7 +377,7 @@
  *                 as large as the size ctx->len of ctx->N (eg. 128 bytes
  *                 if RSA-1024 is used) to be able to hold an arbitrary
  *                 decrypted message. If it is not large enough to hold
- *                 the decryption of the particular ciphertext provided, 
+ *                 the decryption of the particular ciphertext provided,
  *                 the function will return MBEDTLS_ERR_RSA_OUTPUT_TOO_LARGE.
  *
  * \note           The input buffer must be as large as the size
@@ -411,10 +411,10 @@
  *                 as large as the size ctx->len of ctx->N (eg. 128 bytes
  *                 if RSA-1024 is used) to be able to hold an arbitrary
  *                 decrypted message. If it is not large enough to hold
- *                 the decryption of the particular ciphertext provided, 
+ *                 the decryption of the particular ciphertext provided,
  *                 the function will return MBEDTLS_ERR_RSA_OUTPUT_TOO_LARGE.
  *
- * \note           The input buffer must be as large as the size 
+ * \note           The input buffer must be as large as the size
  *                 of ctx->N (eg. 128 bytes if RSA-1024 is used).
  */
 int mbedtls_rsa_rsaes_oaep_decrypt( mbedtls_rsa_context *ctx,
diff --git a/include/mbedtls/ssl.h b/include/mbedtls/ssl.h
old mode 100755
new mode 100644
index 8573283..eeb645c
--- a/include/mbedtls/ssl.h
+++ b/include/mbedtls/ssl.h
@@ -1580,22 +1580,22 @@
 
 #if defined(MBEDTLS_X509_CRT_PARSE_C)
 /**
- * \brief          Set or reset the hostname to check against the received 
- *                 server certificate. It sets the ServerName TLS extension, 
+ * \brief          Set or reset the hostname to check against the received
+ *                 server certificate. It sets the ServerName TLS extension,
  *                 too, if that extension is enabled. (client-side only)
  *
  *
  * \param ssl      SSL context
  * \param hostname the server hostname, may be NULL to clear hostname
- 
+ *
  * \note           Maximum hostname length MBEDTLS_SSL_MAX_HOST_NAME_LEN.
  *
- * \return         0 if successful, MBEDTLS_ERR_SSL_ALLOC_FAILED on 
- *                 allocation failure, MBEDTLS_ERR_SSL_BAD_INPUT_DATA on 
+ * \return         0 if successful, MBEDTLS_ERR_SSL_ALLOC_FAILED on
+ *                 allocation failure, MBEDTLS_ERR_SSL_BAD_INPUT_DATA on
  *                 too long input hostname.
  *
  *                 Hostname set to the one provided on success (cleared
- *                 when NULL). On allocation failure hostname is cleared. 
+ *                 when NULL). On allocation failure hostname is cleared.
  *                 On too long input failure, old hostname is unchanged.
  */
 int mbedtls_ssl_set_hostname( mbedtls_ssl_context *ssl, const char *hostname );