conf: setup to allow building libtiff to support ia32 envs in node (#285)

Author: galkahana

LibTiff/binding.gyp

@@ -30,6 +30,11 @@
                     "defines": [
                         'HAVE_UNISTD_H=1'
                     ]
+                }],
+                ['target_arch == "ia32"', {
+                    "defines": [
+                        'SIZEOF_SIZE_T=4'
+                    ]
                 }]
             ],     
             'include_dirs': [

LibTiff/tif_config.h

@@ -45,8 +45,10 @@
 /* Define to the home page for this package. */
 #define PACKAGE_URL ""
 
-/* Size of size_t */
+/* Size of size_t, allowing external override */
+#ifndef SIZEOF_SIZE_T
 #define SIZEOF_SIZE_T 8
+#endif
 
 
 /** Maximum number of TIFF IFDs that libtiff can iterate through in a file. */