Remove support for AmigaOS

There is a lot of specialized code for supporting AmigaOS and it has
not been maintained for a number of years.  It's highly unlikely that
the latest versions even compile properly on AmigaOS anymore.  After
requesting that someone step forward to own the maintenance of the
port in the GNU Make 4.4 release and getting no takers, I removed it.

* NEWS: Announce the removal.
* README.in: Remove README.Amiga reference.
* README.Amiga: Remove unused file.
* SCOPTIONS: Ditto.
* src/amiga.c: Ditto.
* src/amiga.h: Ditto.
* src/config.ami: Ditto.
* mk/Amiga.mk: Ditto.
* Makefile.am: Remove references to deleted files.
* Basic.mk.template: Ditto.
* maintMakefile: Ditto.
* src/commands.c: Remove ifdef'd Amiga code.
* src/default.c: Ditto.
* src/dir.c: Ditto.
* src/file.c: Ditto.
* src/function.c: Ditto.
* src/job.c: Ditto.
* src/job.h: Ditto.
* src/main.c: Ditto.
* src/os.h: Ditto.
* src/read.c: Ditto.
* src/remake.c: Ditto.

1 files changed, 0 insertions, 2 deletions

diff --git a/README.in b/README.in
index 921c5ea3..229df365 100644
--- a/README.in
+++ b/README.in
@@ -177,8 +177,6 @@ Ports
 
   - See README.VMS for details about GNU Make on OpenVMS.
 
-  - See README.Amiga for details about GNU Make on AmigaDOS.
-
   - See README.zOS for details about GNU Make on z/OS.
 
   - See README.W32 for details about GNU Make on Windows NT, 95, or 98.