testsuite: Move complex tests to their own subdirectory

It seems a bit silly to isolate them by globbing vs "*complex*"
when we can just as easily put them in their own subdirectory.

testsuite/libffi.complex/complex.inc

@@ -0,0 +1,51 @@
+/* -*-c-*-*/
+#include "ffitest.h"
+#include <complex.h>
+
+static _Complex T_C_TYPE f_complex(_Complex T_C_TYPE c, int x, int *py)
+{
+  c = -(2 * creal (c)) + (cimag (c) + 1)* I;
+  *py += x;
+
+  return c;
+}
+
+int main (void)
+{
+  ffi_cif cif;
+  ffi_type *args[MAX_ARGS];
+  void *values[MAX_ARGS];
+
+  _Complex T_C_TYPE tc_arg;
+  _Complex T_C_TYPE tc_result;
+  int tc_int_arg_x;
+  int tc_y;
+  int *tc_ptr_arg_y = &tc_y;
+
+  args[0] = &T_FFI_TYPE;
+  args[1] = &ffi_type_sint;
+  args[2] = &ffi_type_pointer;
+  values[0] = &tc_arg;
+  values[1] = &tc_int_arg_x;
+  values[2] = &tc_ptr_arg_y;
+
+  /* Initialize the cif */
+  CHECK(ffi_prep_cif(&cif, FFI_DEFAULT_ABI, 3,
+		     &T_FFI_TYPE, args) == FFI_OK);
+
+  tc_arg = 1 + 7 * I;
+  tc_int_arg_x = 1234;
+  tc_y = 9876;
+  ffi_call(&cif, FFI_FN(f_complex), &tc_result, values);
+
+  printf ("%f,%fi %f,%fi, x %d 1234, y %d 11110\n",
+	  T_CONV creal (tc_result), T_CONV cimag (tc_result),
+	  T_CONV creal (2.0), T_CONV creal (8.0), tc_int_arg_x, tc_y);
+
+  CHECK (creal (tc_result) == -2);
+  CHECK (cimag (tc_result) == 8);
+  CHECK (tc_int_arg_x == 1234);
+  CHECK (*tc_ptr_arg_y == 11110);
+
+  exit(0);
+}