[PR87054] adjust testcase for 32-bit x86

The test assumed __int128 to be available whenever __SSE__ was
defined, but this assumption doesn't hold on 32-bit x86.  Fixed.

for  gcc/testsuite/ChangeLog

	PR middle-end/87054
	* gcc.dg/pr87054.c: Adjust for no __int128 on x86.

From-SVN: r264526

gcc/testsuite/ChangeLog

+2018-09-24  Alexandre Oliva <oliva@adacore.com>
+
+	PR middle-end/87054
+	* gcc.dg/pr87054.c: Adjust for no __int128 on x86.
+
 2018-09-23  Thomas Koenig  <tkoenig@gcc.gnu.org>
 
 	PR fortran/87395

gcc/testsuite/gcc.dg/pr87054.c

@@ -2,7 +2,7 @@
 // { dg-options "-O2" }
 
 #ifndef T
-# ifdef __SSE__
+# if __SIZEOF_INT128__ && defined __SSE__
 #  define T __int128
 # else
 #  define T long