pythongh-89640: Restore configure error message on failure to detect …

…float word order

Before python#126387, if we didn't detect float word order we'd raise the following
configure error:
```
Unknown float word ordering. You need to manually preset
ax_cv_c_float_words_bigendian=no (or yes) according to your system.
```
This puts it back (except for host_cpu arm or wasm).

configure.ac

@@ -5920,7 +5920,15 @@ AX_C_FLOAT_WORDS_BIGENDIAN(
                                 stored in ARM mixed-endian order (byte order 45670123)])],
            [wasm*], [AC_DEFINE([DOUBLE_IS_LITTLE_ENDIAN_IEEE754], [1],
                                [Define if C doubles are 64-bit IEEE 754 binary format,
-                                stored with the least significant byte first])])])
+                                stored with the least significant byte first])],
+           AC_MSG_ERROR[([
+
+Unknown float word ordering. You need to manually preset
+ax_cv_c_float_words_bigendian=no (or yes) according to your system.
+
+           ])]
+  )]
+)
 
 # The short float repr introduced in Python 3.1 requires the
 # correctly-rounded string <-> double conversion functions from