FreeBSD: Ignore symlink to i386 includes

A symlink to i386 includes is created in the build dir on amd64 since
freebsd/freebsd-src@d07600c

Tell git to ignore it like the other include links.

Reviewed-by: Brian Behlendorf <[email protected]>
Signed-off-by: Ryan Moeller <[email protected]>
Closes openzfs#13719

Author: Ryan Moeller

module/.gitignore

@@ -22,5 +22,6 @@
 /export_syms
 /machine
 /x86
+/i386
 
 !Makefile.in