Corected some issues with jar_xm

Problems when compiling with VS2015
Probably DEBUG(...) macro is not the best naming...

src/external/jar_xm.h

@@ -308,7 +308,7 @@ uint64_t jar_xm_get_remaining_samples(jar_xm_context_t* ctx);
 #include <math.h>
 #include <string.h>
 
-#ifdef JAR_XM_DEBUG
+#if JAR_XM_DEBUG            //JAR_XM_DEBUG defined as 0
 #include <stdio.h>
 #define DEBUG(fmt, ...) do {                                        \
         fprintf(stderr, "%s(): " fmt "\n", __func__, __VA_ARGS__);    \
@@ -782,7 +782,7 @@ uint64_t jar_xm_get_latest_trigger_of_channel(jar_xm_context_t* ctx, uint16_t ch
 #define READ_U32(offset) ((uint32_t)READ_U16(offset) | ((uint32_t)READ_U16((offset) + 2) << 16))
 #define READ_MEMCPY(ptr, offset, length) memcpy_pad(ptr, length, moddata, moddata_length, offset)
 
-static inline void memcpy_pad(void* dst, size_t dst_len, const void* src, size_t src_len, size_t offset) {
+static void memcpy_pad(void* dst, size_t dst_len, const void* src, size_t src_len, size_t offset) {
     uint8_t* dst_c = dst;
     const uint8_t* src_c = src;