Fix missing-prototype error in programs/fuzz by moving LLVMFuzzerTestOneInput prototype to common.h

Signed-off-by: Michael Schuster <michael@schuster.ms>

programs/fuzz/common.h

@@ -23,3 +23,6 @@ int dummy_random(void *p_rng, unsigned char *output, size_t output_len);
 int dummy_entropy(void *data, unsigned char *output, size_t len);
 int fuzz_recv_timeout(void *ctx, unsigned char *buf, size_t len,
                       uint32_t timeout);
+
+/* Implemented in the fuzz_*.c sources and required by onefile.c */
+int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size);

programs/fuzz/fuzz_pkcs7.c

@@ -1,5 +1,6 @@
 #include <stdint.h>
 #include "mbedtls/pkcs7.h"
+#include "common.h"
 
 int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size)
 {

programs/fuzz/fuzz_pubkey.c

@@ -1,6 +1,7 @@
 #include <stdint.h>
 #include <stdlib.h>
 #include "mbedtls/pk.h"
+#include "common.h"
 
 int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size)
 {

programs/fuzz/fuzz_x509crl.c

@@ -1,5 +1,6 @@
 #include <stdint.h>
 #include "mbedtls/x509_crl.h"
+#include "common.h"
 
 int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size)
 {

programs/fuzz/fuzz_x509crt.c

@@ -1,5 +1,6 @@
 #include <stdint.h>
 #include "mbedtls/x509_crt.h"
+#include "common.h"
 
 int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size)
 {

programs/fuzz/fuzz_x509csr.c

@@ -1,5 +1,6 @@
 #include <stdint.h>
 #include "mbedtls/x509_csr.h"
+#include "common.h"
 
 int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size)
 {

programs/fuzz/onefile.c

@@ -1,14 +1,13 @@
 #include <stdint.h>
 #include <stdlib.h>
 #include <stdio.h>
+#include "common.h"
 
 /* This file doesn't use any Mbed TLS function, but grab mbedtls_config.h anyway
  * in case it contains platform-specific #defines related to malloc or
  * stdio functions. */
 #include "mbedtls/build_info.h"
 
-int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size);
-
 int main(int argc, char **argv)
 {
     FILE *fp;