sim: Add dlsym to nuttx-names.in

```
    Program received signal SIGSEGV, Segmentation fault.
    getpid () at task/task_getpid.c:76
    76      task/task_getpid.c: No such file or directory.
    rax            0x2feeb4            3141300
    rbx            0xc53f83            12926851
    rcx            0x6837665ee4c00     1833394399759360
    rdx            0x472080            4661376
    rsi            0xc53f83            12926851
    rdi            0xffffffffffffffff  -1
    rbp            0x7ffe4cdfe140      0x7ffe4cdfe140
    rsp            0x7ffe4cdfe0f0      0x7ffe4cdfe0f0
    r8             0xffffffffffffffff  -1
    r9             0x0                 0
    r10            0x22                34
    r11            0x246               582
    r12            0x472080            4661376
    r13            0x7ffe4cdfe3e8      140730188162024
    r14            0x472080            4661376
    r15            0xf60398            16122776
    rip            0x4e9b93            0x4e9b93 <getpid+35>
    eflags         0x10206             [ PF IF RF ]
    cs             0x33                51
    ss             0x2b                43
    ds             0x0                 0
    es             0x0                 0
    fs             0x0                 0
    gs             0x0                 0
    #0  getpid () at task/task_getpid.c:76
    apache#1  0x00000000006ad25a in modlib_registry_lock () at modlib/modlib_registry.c:89
    apache#2  0x0000000000c3648d in modsym (handle=0xffffffffffffffff, name=0xc53f83 "mmap") at module/mod_modsym.c:77
    apache#3  0x0000000000c2cd3a in dlsym (handle=0xffffffffffffffff, name=0xc53f83 "mmap") at dlfcn/lib_dlsym.c:149
    apache#4  0x00000000004a0034 in __interception::InterceptFunction(char const*, unsigned long*, unsigned long, unsigned long) ()
    apache#5  0x000000000048181e in InitializeCommonInterceptors() ()
    apache#6  0x000000000048106a in __asan::InitializeAsanInterceptors() ()
    apache#7  0x000000000049b85e in __asan::AsanInitInternal() ()
    apache#8  0x00007f09cfb04ce6 in ?? () from /lib64/ld-linux-x86-64.so.2
    apache#9  0x00007f09cfaf413a in ?? () from /lib64/ld-linux-x86-64.so.2
    apache#10 0x0000000000000001 in ?? ()
    apache#11 0x00007ffe4cdfff56 in ?? ()
    apache#12 0x0000000000000000 in ?? ()
```

arch/sim/src/nuttx-names.in

@@ -38,6 +38,7 @@ NXSYMBOLS(clock_gettime)
 NXSYMBOLS(close)
 NXSYMBOLS(closedir)
 NXSYMBOLS(connect)
+NXSYMBOLS(dlsym)
 NXSYMBOLS(dup)
 NXSYMBOLS(exit)
 NXSYMBOLS(free)