patch 8.2.1648: Amiga: no common build file for Amiga (-like) systems

Problem:    Amiga: no common build file for Amiga (-like) systems.
Solution:   Turn Make_morph.mak into Make_ami.mak. (Ola Söder, closes #6805)
diff --git a/Filelist b/Filelist
index 12b973f..a094634 100644
--- a/Filelist
+++ b/Filelist
@@ -623,7 +623,7 @@
 		README_amisrc.txt.info \
 		src.info \
 		src/INSTALLami.txt \
-		src/Make_morph.mak \
+		src/Make_ami.mak \
 		src/os_amiga.c \
 		src/os_amiga.h \
 		src/proto/os_amiga.pro \