[process info] Remove assert in DoGetGroupName

Summary:
Disabling this assert prevents lldb-server from crashing, which prevents it from finding the user and group names of a given process list.

Before this change, the process list didn't contain names:

```
PID    PARENT USER       GROUP      EFF USER   EFF GROUP  TRIPLE                               ARGUMENTS
====== ====== ========== ========== ========== ========== ============================== ============================
27585  982    10098      10098      10098      10098                                     com.LogiaGroup.LogiaDeck
27623  982    10098      10098      10098      10098                                     com.digitalturbine.ignite.suspend.DataUsageRecorderService
28024  982    10199      10199      10199      10199                                     com.google.vr.vrcore
28061  983    10353      10353      10353      10353                                     com.instagram.android:videoplayer
28121  982    10045      10045      10045      10045                                     com.sec.spp.push
28325  982    10247      10247      10247      10247                                     com.facebook.orca
28714  982    10367      10367      10367      10367                                     com.samsung.android.dialer
29867  3208   2000       2000       2000       2000       aarch64-unknown-linux-android  /system/bin/sh-c /data/local/tmp/lldb-server platform --listen *:5557 --server --log-file /data/local/tmp/logs --log-channels gdb-remote all --log-channels lldb all
```

After this change, the list looks much better

```
PID    PARENT USER       GROUP      EFF USER   EFF GROUP  TRIPLE                               ARGUMENTS
====== ====== ========== ========== ========== ========== ============================== ============================
24459  1      wifi       1010       wifi       1010       aarch64-unknown-linux-android  /vendor/bin/hw/wpa_supplicant-O/data/vendor/wifi/wpa/sockets -puse_p2p_group_interface=1 -g@android:wpa_wlan0
25098  982    u0_a42     10042      u0_a42     10042                                     com.samsung.android.messaging
25442  982    u0_a65     10065      u0_a65     10065                                     com.samsung.android.mobileservice
25974  982    u0_a9      10009      u0_a9      10009                                     com.samsung.android.contacts
26377  982    radio      1001       radio      1001                                      com.samsung.android.incallui
26390  983    u0_a26     10026      u0_a26     10026                                     com.samsung.android.game.gametools
26876  983    u0_a306    10306      u0_a306    10306                                     com.tencent.mm:push
```

Reviewers: clayborg,aadsm,xiaobai,labath

Subscribers:

llvm-svn: 373760