Added support for tuple return with __asmtuple!(int,int) etc.

tests/mini/__asm1.d

@@ -0,0 +1,22 @@
+import ldc.llvmasm;
+void main() {
+    version(X86)
+    {
+        int i;
+        __asm("movl $1, $0", "=*m,i", &i, 42);
+        assert(i == 42);
+
+        int j = __asm!(int)("movl $1, %eax", "={ax},i", 42);
+        assert(j == 42);
+
+        auto k = __asmtuple!(int,int)("mov $2, %eax ; mov $3, %edx", "={ax},={dx},i,i", 10, 20);
+        assert(k.v[0] == 10);
+        assert(k.v[1] == 20);
+    }
+    else version(PPC)
+    {
+        int j = 42;
+        int i = __asm!(int)("li $1, $0", "=r,*m", &j);
+        assert(i == 42);
+    }
+}