Match and link printf.c

libc/string.h

@@ -19,6 +19,7 @@ char* strncpy(char* dest, const char* src, size_t num);
 int strcmp(const char* s1, const char* s2);
 int strncmp(const char* s1, const char* s2, size_t n);
 char* strncat(char* dest, const char* src, size_t n);
+char* strchr(const char* str, int chr);
 
 #ifdef __cplusplus
 }