Fix static compilation with Visual C.

* include/freetype/internal/compiler-macros.h
(FT_INTERNAL_FUNCTION_ATTRIBUTE) <_WIN32>: Define as empty.

ChangeLog

@@ -1,3 +1,10 @@
+2020-07-28  Anuj Verma  <anujv@iitbhilai.ac.in>
+
+	Fix static compilation with Visual C.
+
+	* include/freetype/internal/compiler-macros.h
+	(FT_INTERNAL_FUNCTION_ATTRIBUTE) <_WIN32>: Define as empty.
+
 2020-07-28  Priyesh Kumar  <priyeshkkumar@gmail.com>
 
 	Fix `-Wformat' compiler warnings.

include/freetype/internal/compiler-macros.h

@@ -105,9 +105,16 @@ FT_BEGIN_HEADER
    * generate smaller and faster code on ELF-based platforms.  Place this
    * before a function declaration.
    */
-#if ( defined( __GNUC__ ) && __GNUC__ >= 4 ) || defined( __clang__ )
+
+  /* Visual C, mingw */
+#if defined( _WIN32 )
+#define FT_INTERNAL_FUNCTION_ATTRIBUTE  /* empty */
+
+  /* gcc, clang */
+#elif ( defined( __GNUC__ ) && __GNUC__ >= 4 ) || defined( __clang__ )
 #define FT_INTERNAL_FUNCTION_ATTRIBUTE  \
           __attribute__(( visibility( "hidden" ) ))
+
 #else
 #define FT_INTERNAL_FUNCTION_ATTRIBUTE  /* empty */
 #endif