use MAX_CIPHER_BLOCK_SIZE more consistently
no need to define _gnutls_x86_cpuid_s
use __hidden in solaris to provide the hidden visibility attribute
if receiving a ChangeCipherSpec fails, return GNUTLS_E_UNEXPECTED_PACKET

That is more precise than the current GNUTLS_E_UNEXPECTED_PACKET_LENGTH
guile: doc: Make it clear that the bindings are part of GnuTLS.
Add NEWS entry for Guile changes.
guile: doc: Remove erroneous @ifnottex.