arm: do not use ram_size global

Use the machine properties instead.

Cc: qemu-ppc@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/target/arm/arm-semi.c b/target/arm/arm-semi.c
index c892e0e..f7b7bff 100644
--- a/target/arm/arm-semi.c
+++ b/target/arm/arm-semi.c
@@ -37,6 +37,7 @@
 #include "exec/gdbstub.h"
 #include "qemu/cutils.h"
 #include "hw/arm/boot.h"
+#include "hw/boards.h"
 #endif
 
 #define TARGET_SYS_OPEN        0x01
@@ -1048,7 +1049,7 @@
             retvals[2] = ts->stack_base;
             retvals[3] = 0; /* Stack limit.  */
 #else
-            limit = ram_size;
+            limit = current_machine->ram_size;
             /* TODO: Make this use the limit of the loaded application.  */
             retvals[0] = rambase + limit / 2;
             retvals[1] = rambase + limit;