Remove extern int references to errno and rely on the #include

Fixes compilation against glibc-2.3+.

[Description and fix to error.3 by Ismael Luceno <ismael@iodev.co.uk>]
Import jms1 6ce
Import jms1 6cf
Import jms1 6cg
Import jms1 7
Import jms1 7.01
Import jms1 7.02
Import jms1 7.03
Import jms1 7.04
Import jms1 7.05
Import jms1 7.06
Import jms1 7.07
Import jms1 7.08
Import jms1 7.10