Fix format string conversion specifiers

[imaami]

Signed-off-by: Juuso Alasuutari [email protected]

[imaami]

@AlexeyAB This fixes all the incorrect printf format string conversion specifiers I could find. At least one of them in src/http_stream.cpp may cause a garbage value to be printed in the HTTP header's Content-Length unless it's fixed, because it will read 8 bytes from the stack even though the integer at that location is 4 bytes long.