[PATCH] newlib: update nds32 configure checks

This subdir doesn't link any code, so there's no need to require
AC_NO_EXECUTABLES, and no other dir uses this either.  Punt it.

The two tests in here are using compile tests to look for some
preprocessor defines, but we don't need to compile the code,
just preprocess it.  So switch to AC_PREPROC_IFELSE.
---
 newlib/libm/machine/nds32/Makefile.in  |   1 +
 newlib/libm/machine/nds32/configure    | 266 +++++++++++++++++--------
 newlib/libm/machine/nds32/configure.ac |   5 +-
 3 files changed, 186 insertions(+), 86 deletions(-)
 mode change 100644 => 100755 newlib/libm/machine/nds32/configure

diff --git a/newlib/libm/machine/nds32/configure.ac b/newlib/libm/machine/nds32/configure.ac
index 7d49c9ae20bf..d4c5f49a2625 100644
--- a/newlib/libm/machine/nds32/configure.ac
+++ b/newlib/libm/machine/nds32/configure.ac
@@ -11,8 +11,7 @@ NEWLIB_CONFIGURE(../../..)
 
 
 dnl Use builtin macro to detect if FPU extension support is on.
-AC_NO_EXECUTABLES
-AC_COMPILE_IFELSE([AC_LANG_PROGRAM(
+AC_PREPROC_IFELSE([AC_LANG_PROGRAM(
 [[#if (__NDS32_EXT_FPU_SP__)
 warning: Has nds32 FPU SP extension support
 #endif
@@ -21,7 +20,7 @@ warning: Has nds32 FPU SP extension support
 		  [has_nds32_fpu_sp="yes"])
 AM_CONDITIONAL(HAS_NDS32_FPU_SP, test "$has_nds32_fpu_sp" = "yes")
 
-AC_COMPILE_IFELSE([AC_LANG_PROGRAM(
+AC_PREPROC_IFELSE([AC_LANG_PROGRAM(
 [[#if (__NDS32_EXT_FPU_DP__)
 warning: Has nds32 FPU DP extension support
 #endif
-- 
2.34.1