math: Fix log10f on some ABIs

The commit 9247f53219 triggered some regressions on loongarch and
riscv:

math/test-float-log10
math/test-float32-log10

And it is due a wrong sync with CORE-MATH for special 0.0/-0.0
inputs.

Checked on aarch64-linux-gnu and loongarch64-linux-gnu-lp64d.

sysdeps/ieee754/flt-32/e_log10f.c

@@ -37,9 +37,8 @@ as_special (float x)
     return x; /* +inf */
   uint32_t ax = ux << 1;
   if (ax == 0u)
-    { /* -0.0 */
-      __math_divzerof (1);
-    }
+    /* -0.0 */
+    return  __math_divzerof (1);
   if (ax > 0xff000000u)
     return x + x; /* nan */
   return __math_invalidf (x);