Update paths of scripts to allow building on BSD

Prior to this change, the assumption in all shell and Python scripts was
that the Bash interpreter would always be available at `/bin/bash`, and
Python would always be available at `/usr/bin/python`. However, on a VM
running FreeBSD, installing bash and python using the pkg command
installs them under /usr/local/bin.

This change updates the paths to use /usr/bin/env in the shebang. While
this is not a standard path either, it is more likely to be available at
this location.

This change also updates the find command in common_infra.sh to use
`-perm -+x` in lieu of `-executable`, which is not a condition defined
by POSIX. This allows running the tests on BSD.

lib/libx52util/x52_char_map_gen.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 # Character map generator
 #
 # Copyright (C) 2012-2018 Nirenjan Krishnan (nirenjan@nirenjan.org)

tests/common_infra.sh

@@ -79,7 +79,7 @@ find_programs()
     fi
 
     # Find the X52cli script
-    X52CLI=$(find .. -path '*/cli/x52cli' -executable)
+    X52CLI=$(find .. -path '*/cli/x52cli' -perm -+x)
 
     if [[ -z "$X52CLI" ]]
     then
@@ -87,14 +87,14 @@ find_programs()
     fi
 
     # Find the x52test_log_actions program
-    X52LOGACT=$(find .. -path '*/libusbx52/x52test_log_actions' -executable)
+    X52LOGACT=$(find .. -path '*/libusbx52/x52test_log_actions' -perm -+x)
     if [[ -z "$X52LOGACT" ]]
     then
         exit 1
     fi
 
     # Find the x52test_create_device_list program
-    X52DEVLIST=$(find .. -path '*/libusbx52/x52test_create_device_list' -executable)
+    X52DEVLIST=$(find .. -path '*/libusbx52/x52test_create_device_list' -perm -+x)
     if [[ -z "$X52DEVLIST" ]]
     then
         exit 1

tests/libx52/test_brightness

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 # MFD & LED brightness tests
 #
 # Copyright (C) 2012-2018 Nirenjan Krishnan (nirenjan@nirenjan.org)

tests/libx52/test_clock

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 # Clock tests
 #
 # Copyright (C) 2012-2018 Nirenjan Krishnan (nirenjan@nirenjan.org)

tests/libx52/test_indicator

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 # Indicator (blink & shift) tests
 #
 # Copyright (C) 2012-2018 Nirenjan Krishnan (nirenjan@nirenjan.org)

tests/libx52/test_leds

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 # LED tests
 #
 # Copyright (C) 2012-2018 Nirenjan Krishnan (nirenjan@nirenjan.org)

tests/libx52/test_mfd

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 # MFD tests
 #
 # Copyright (C) 2012-2018 Nirenjan Krishnan (nirenjan@nirenjan.org)

tests/libx52/test_timezone

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 # Timezone tests
 #
 # Copyright (C) 2020 Nirenjan Krishnan (nirenjan@nirenjan.org)