[libxml2] cmake: remove unused checks

[Nick Wellnhofer <nwellnhof src gnome org>]

commit 0aad075c6b090b6e3d1413951e3a5f34780435b7
Author: Ben Boeckel <ben boeckel kitware com>
Date:   Mon Jul 26 20:10:52 2021 -0400

    cmake: remove unused checks
    
    Even the configured `config.h` did not forward the results of these
    checks.

 CMakeLists.txt | 4 ----
 1 file changed, 4 deletions(-)
---
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 7e9483f8..369a5c2f 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -166,11 +166,9 @@ else()
        check_include_files(dl.h HAVE_DL_H)
        check_include_files(errno.h HAVE_ERRNO_H)
        check_include_files(fcntl.h HAVE_FCNTL_H)
-       check_function_exists(finite HAVE_FINITE)
        check_include_files(float.h HAVE_FLOAT_H)
        check_function_exists(fpclass HAVE_FPCLASS)
        check_function_exists(fprintf HAVE_FPRINTF)
-       check_function_exists(fp_class HAVE_FP_CLASS)
        check_function_exists(ftime HAVE_FTIME)
        check_function_exists(getaddrinfo HAVE_GETADDRINFO)
        check_function_exists(gettimeofday HAVE_GETTIMEOFDAY)
@@ -178,9 +176,7 @@ else()
        check_function_exists(isascii HAVE_ISASCII)
        check_function_exists(isinf HAVE_ISINF)
        check_function_exists(isnan HAVE_ISNAN)
-       check_function_exists(isnand HAVE_ISNAND)
        check_library_exists(history append_history "" HAVE_LIBHISTORY)
-       check_library_exists(lzma lzma_code "" HAVE_LIBLZMA)
        check_library_exists(pthread pthread_join "" HAVE_LIBPTHREAD)
        check_library_exists(readline readline "" HAVE_LIBREADLINE)
        check_library_exists(z gzread "" HAVE_LIBZ)