[PATCH 1/4] build: work around bash issue

[Jan Beulich <jbeulich@xxxxxxxx>]

Older bash fails to honor "set -e" for certain built-in commands
("while" here), despite the command's status correctly bein non-zero.
The subsequent objcopy invocation now being separated by a semicolon
results in no failure. Insert an explicit "exit" (replacing ; by &&
ought to be another possible workaround).

Fixes: e321576f4047 ("xen/build: start using if_changed")
Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
---
I've done a pretty light-weight audit of possible further instances of
this issue, but didn't find any.

--- a/xen/Rules.mk
+++ b/xen/Rules.mk
@@ -193,7 +193,7 @@ define cmd_obj_init_o
             echo "Error: size of $<:$$name is 0x$$sz" >&2; \
             exit $$(expr $$idx + 1);; \
         esac; \
-    done; \
+    done || exit $$?; \
     $(OBJCOPY) $(foreach s,$(SPECIAL_DATA_SECTIONS),--rename-section 
.$(s)=.init.$(s)) $< $@
 endef