httpd: code shrink

Use decode_base64() from uuencode.c when uudecode/base64 applets are included.
That function is bigger than httpd's decodeBase64(), so we use the old one when
those applets are disabled. Bloat-o-meter when one of those is enabled:

function                                             old     new   delta
handle_incoming_and_exit                            2371    2265    -106

Signed-off-by: Xabier Oneca <xoneca@gmail.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
1 file changed