common: Drop part.h from common header

Move this uncommon header out of the common header.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/fastboot/fb_getvar.c b/drivers/fastboot/fb_getvar.c
index 467a861..52da34b 100644
--- a/drivers/fastboot/fb_getvar.c
+++ b/drivers/fastboot/fb_getvar.c
@@ -10,6 +10,7 @@
 #include <fb_mmc.h>
 #include <fb_nand.h>
 #include <fs.h>
+#include <part.h>
 #include <version.h>
 
 static void getvar_version(char *var_parameter, char *response);