Remove unused macros

Cleanup of ecede0bc72

config.cmake.h.in

@@ -65,12 +65,6 @@
 /* Define to 1 if you have the <cpuid.h> header file. */
 #cmakedefine HAVE_CPUID_H
 
-/* Define to 1 if C++ supports variable-length arrays. */
-#cmakedefine HAVE_CXX_VARARRAYS
-
-/* Define to 1 if C supports variable-length arrays. */
-#cmakedefine HAVE_C_VARARRAYS
-
 /* Define to 1 if fseeko (and presumably ftello) exists and is declared. */
 #cmakedefine HAVE_FSEEKO
 
@@ -161,9 +155,6 @@
 /* The size of `void*', as computed by sizeof. */
 #cmakedefine SIZEOF_VOIDP
 
-/* Define to 1 if you have the ANSI C header files. */
-#cmakedefine STDC_HEADERS
-
 /* Enable extensions on AIX 3, Interix.  */
 #ifndef _ALL_SOURCE
 #define _ALL_SOURCE

src/libFLAC++/CMakeLists.txt

@@ -1,17 +1,3 @@
-check_cxx_source_compiles("
-    #ifdef __STDC_NO_VLA__
-    syntax error;
-    #else
-    int fvla (int m, int * c)
-    {
-      int D[m];
-      return D[0] == c[0];
-    }
-
-    int main(int, char * []) { return 0; }
-    #endif"
-    HAVE_CXX_VARARRAYS)
-
 add_library(FLAC++
     metadata.cpp
     stream_decoder.cpp