Bug#943751: lz4: LZ4_*_destSize() fix for debian lz4 stable versions

[Gao Xiang]

Here is a bug reproducer for this issue, please consider backporting
them... It has real affect on *_destSize lz4 users.

bug.c (crash if liblz4 < 1.9.2)

#include <lz4.h>
#include <string.h>
#include <stdio.h>
#include <unistd.h>
#include <fcntl.h>

#define SRCSIZE         1045934

int main(void)
{

        int SrcSize = SRCSIZE;
        char buf[SRCSIZE] = {0};
        char dst[4096];
        int compressed;

        compressed = LZ4_compress_destSize(buf, dst, &SrcSize, 4096);
        printf("compressed: %d SrcSize: %d", compressed, SrcSize);
        return 0;
}