Fix PositionIndependentTargets test with clang trunk.

The __PIE__ define might be set instead of __PIC__ if fPIE is used.

http://llvm.org/bugs/show_bug.cgi?id=13221

Tests/PositionIndependentTargets/pic_test.h

@@ -1,7 +1,7 @@
 
 #if defined(__ELF__)
-#  if !defined(__PIC__)
-#    error "The POSITION_INDEPENDENT_CODE property should cause __PIC__ to be defined on ELF platforms."
+#  if !defined(__PIC__) && !defined(__PIE__)
+#    error "The POSITION_INDEPENDENT_CODE property should cause __PIC__ or __PIE__ to be defined on ELF platforms."
 #  endif
 #endif