Two potential deadlock errors due to the unreleased lock &mutex_mmap
Dear developers:
             Thank you for your checking. Similarly, in the function AllocDynarecMap, the lock &mutex_mmap also may not be released.  The fix is to insert pthread_mutex_unlock(&mutex_mmap); before returning.

https://github.com/ptitSeb/box64/blob/f000951fc970708bfa0dd5d357a334b8cfc41eb0/src/custommem.c#L436



```
uintptr_t AllocDynarecMap(dynablock_t* db, size_t size)
{
    if(!size)
        return 0;
    if(size>MMAPSIZE-2*sizeof(blockmark_t)) {
        #ifndef USE_MMAP
        pthread_mutex_lock(&mutex_mmap);  // here
        void *p = NULL;
        if(posix_memalign(&p, box64_pagesize, size)) {
            dynarec_log(LOG_INFO, "Cannot create dynamic map of %zu bytes\n", size);
            return 0;   // return without releasing
        }
        mprotect(p, size, PROT_READ | PROT_WRITE | PROT_EXEC);
        #else
        void* p = mmap(NULL, size, PROT_READ|PROT_WRITE|PROT_EXEC, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
        if(p==(void*)-1) {
            dynarec_log(LOG_INFO, "Cannot create dynamic map of %zu bytes\n", size);
            return 0;  // return without releasing
        }
        #endif
        ...;

    return ret;
}
```


Best,