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

programs/ssl/ssl_client1.c

@@ -30,7 +30,7 @@
 #else
 #include <stdio.h>
 #include <stdlib.h>
-#define mbedtls_time       time 
+#define mbedtls_time       time
 #define mbedtls_time_t     time_t
 #define mbedtls_fprintf    fprintf
 #define mbedtls_printf     printf

programs/ssl/ssl_mail_client.c

@@ -31,7 +31,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #define mbedtls_time       time
-#define mbedtls_time_t     time_t 
+#define mbedtls_time_t     time_t
 #define mbedtls_fprintf    fprintf
 #define mbedtls_printf     printf
 #endif

programs/ssl/ssl_server.c

@@ -31,7 +31,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #define mbedtls_time       time
-#define mbedtls_time_t     time_t 
+#define mbedtls_time_t     time_t
 #define mbedtls_fprintf    fprintf
 #define mbedtls_printf     printf
 #endif