In musl this is not pulled in automatically

Bug: https://bugs.gentoo.org/713220
Bug: https://bugs.gentoo.org/896204

#  Pascal Jäger <pascal.jaeger@leimstift.de> (2023-09-22)

--- a/dcraw.c
+++ b/dcraw.c
@@ -41,6 +41,7 @@
 #include <string.h>
 #include <time.h>
 #include <sys/types.h>
+#include <locale.h>
 
 #if defined(DJGPP) || defined(__MINGW32__)
 #define fseeko fseek