building with openssl 0.9.7

[Marco d'Itri]

openssl/e_os.h has been removed and get_last_socket_error does not exist
anymore. This header should not have been used anyway, as in the first
lines has this comment:

/* <openssl/e_os2.h> contains what we can justify to make visible
 * to the outside; this file e_os.h is not part of the exported
 * interface. */


I fixed this by removing calls to the function (which is not needed on
UNIX).

-- 
ciao,
Marco