ax_declspec.m4: Fix two line test description to be just one line.

configure: Regenerate.

Author: wilx

configure

@@ -7168,10 +7168,8 @@ fi
 
 if ${continue_checks+:} false; then :
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for __attribute__((visibility(\"default\")))
-  and __attribute__((visibility(\"hidden\")))" >&5
-$as_echo_n "checking for __attribute__((visibility(\"default\")))
-  and __attribute__((visibility(\"hidden\")))... " >&6; }
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for __attribute__((visibility(\"default\"))) and __attribute__((visibility(\"hidden\")))" >&5
+$as_echo_n "checking for __attribute__((visibility(\"default\"))) and __attribute__((visibility(\"hidden\")))... " >&6; }
 if ${ac_cv__attribute__visibility+:} false; then :
   $as_echo_n "(cached) " >&6
 else

m4/ax_declspec.m4

@@ -76,8 +76,8 @@ dnl This typically succeeds on *NIX platforms with GCC or Clang.
 
 AS_VAR_SET_IF([continue_checks],
 [
-AC_CACHE_CHECK([for __attribute__((visibility("default")))
-  and __attribute__((visibility("hidden")))], [ac_cv__attribute__visibility],
+AC_CACHE_CHECK([for __attribute__((visibility("default")))dnl
+ and __attribute__((visibility("hidden")))], [ac_cv__attribute__visibility],
 [
   AC_COMPILE_IFELSE(
     [AC_LANG_PROGRAM(