Give example for configuration in tramp.texi

* doc/misc/tramp.texi (Configuration): Explain how to call Tramp
configuration functions in the init file.
1 job for master in 40 minutes and 11 seconds (queued for 1 second)
Status Job ID Name Coverage
failed #1183


Name Stage Failure
test-all Test
Makefile:313: recipe for target 'check-doit' failed
make[2]: *** [check-doit] Error 2
make[2]: Leaving directory '/builds/emacs/emacs/test'
Makefile:288: recipe for target 'check-expensive' failed
make[1]: Leaving directory '/builds/emacs/emacs/test'
make[1]: *** [check-expensive] Error 2
Makefile:962: recipe for target 'check-expensive' failed
make: *** [check-expensive] Error 2
ERROR: Job failed: exit code 1