Don't check for __has_include

It's standard as part of C++17 apparently.

Bug: 42290600
Change-Id: Ibc2a990c5c7937fee5c096e7e0540a5cf853566a
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/74487
Reviewed-by: Adam Langley <agl@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
diff --git a/include/openssl/span.h b/include/openssl/span.h
index 46c5c6c..fa77962 100644
--- a/include/openssl/span.h
+++ b/include/openssl/span.h
@@ -27,11 +27,9 @@
 #include <string_view>
 #include <type_traits>
 
-#if defined(__has_include)
 #if __has_include(<version>)
 #include <version>
 #endif
-#endif
 
 #if defined(__cpp_lib_ranges) && __cpp_lib_ranges >= 201911L
 #include <ranges>
diff --git a/pki/input.h b/pki/input.h
index 9337d38..65f0102 100644
--- a/pki/input.h
+++ b/pki/input.h
@@ -14,11 +14,9 @@
 #include <openssl/base.h>
 #include <openssl/span.h>
 
-#if defined(__has_include)
 #if __has_include(<version>)
 #include <version>
 #endif
-#endif
 
 #if defined(__cpp_lib_ranges) && __cpp_lib_ranges >= 201911L
 #include <ranges>