tests/avocado: Remove p7zip binary availability check

The single use of the 7z binary has been removed in commit a30e114f3
("tests/acceptance: remove Armbian 19.11.3 test for orangepi-pc"),
we don't need to check for this binary availability anymore.

Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Joaquin de Andres <me@xcancerberox.com.ar>
Reviewed-by: Willian Rampazzo <willianr@redhat.com>
Message-Id: <20211106091059.465109-1-philmd@redhat.com>

tests/avocado/boot_linux_console.py

@@ -22,13 +22,6 @@
 from avocado_qemu import wait_for_console_pattern
 from avocado.utils import process
 from avocado.utils import archive
-from avocado.utils.path import find_command, CmdNotFoundError
-
-P7ZIP_AVAILABLE = True
-try:
-    find_command('7z')
-except CmdNotFoundError:
-    P7ZIP_AVAILABLE = False
 
 """
 Round up to next power of 2