patch 9.1.0431: eval.c is too long

Problem:  eval.c is too long
Solution: Move garbage collection code to new gc.c file
          (Yegappan Lakshmanan)

closes: #14824

Signed-off-by: Yegappan Lakshmanan <yegappan@yahoo.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/Make_ami.mak b/src/Make_ami.mak
index 9e9ebe3..09cdd3c 100644
--- a/src/Make_ami.mak
+++ b/src/Make_ami.mak
@@ -114,6 +114,7 @@
 	float.c \
 	fold.c \
 	getchar.c \
+	gc.c \
 	hardcopy.c \
 	hashtab.c \
 	help.c \