mysqld_qslower-bpfcc does not work on Ubuntu 20.04.1

mysqld_qslower-bpfcc script fails to run on Ubuntu 20.04.1 with the following error

```
Traceback (most recent call last):
File "/usr/sbin/mysqld_qslower-bpfcc", line 97, in
u.enable_probe(probe="query__start", fn_name="do_start")
File "/usr/lib/python3/dist-packages/bcc/usdt.py", line 151, in enable_probe
raise USDTException(
bcc.usdt.USDTException: failed to enable probe 'query__start'; a possible cause can be that the probe requires a pid to enable

```

```
the USDT probes are available in the mariadb 10.6.12 version I am using.

./tplist-bpfcc -p 3126532 | grep query
b'/proc/3126532/root/usr/sbin/mariadbd' b'mysql':b'query__exec__start'
b'/proc/3126532/root/usr/sbin/mariadbd' b'mysql':b'query__exec__done'
b'/proc/3126532/root/usr/sbin/mariadbd' b'mysql':b'query__cache__miss'
b'/proc/3126532/root/usr/sbin/mariadbd' b'mysql':b'query__cache__hit'
b'/proc/3126532/root/usr/sbin/mariadbd' b'mysql':b'query__start'
b'/proc/3126532/root/usr/sbin/mariadbd' b'mysql':b'query__done'
b'/proc/3126532/root/usr/sbin/mariadbd' b'mysql':b'query__parse__start'
b'/proc/3126532/root/usr/sbin/mariadbd' b'mysql':b'query__parse__done'

```

Start by reproducing mysqld_qslower-bpfcc on Ubuntu 20.04.1 with MariaDB 10.6.12 and inspect the probe setup at /usr/lib/python3/dist-packages/bcc/usdt.py. Compare the script's query__start probe with the probes listed by tplist-bpfcc -p; done means the script enables the available probe and runs without the reported USDTException.

Written by the indexing model from the issue text.