meta-bletchley: introduce Bletchley common functions

Add a common functions script for reusing the functions which are
called frequently.

This patch depends on the patchs below:
* https://lore.kernel.org/all/20220613095150.21917-4-potin.lai.pt@gmail.com/

Signed-off-by: Potin Lai <potin.lai@quantatw.com>
Change-Id: I6e1602b00f1b0a19e77506be6eabe18c796e52fe
diff --git a/meta-facebook/meta-bletchley/recipes-bletchley/plat-svc/files/bletchley-early-sys-init b/meta-facebook/meta-bletchley/recipes-bletchley/plat-svc/files/bletchley-early-sys-init
index 2d41c94..a0b5c5a 100755
--- a/meta-facebook/meta-bletchley/recipes-bletchley/plat-svc/files/bletchley-early-sys-init
+++ b/meta-facebook/meta-bletchley/recipes-bletchley/plat-svc/files/bletchley-early-sys-init
@@ -1,61 +1,7 @@
 #!/bin/bash -e
 
-set_gpio()
-{
-    NET_NAME=$1
-    OUT_VAL=$2
-    mapfile -t -d " " GPIO_INFO < <(gpiofind "$NET_NAME")
-    if [ "${#GPIO_INFO[@]}" -ne 2 ]; then
-        echo "set_gpio: can not find gpio, $NET_NAME"
-        return 1
-    fi
-
-    echo -n "set_gpio: set $NET_NAME = $OUT_VAL"
-    if ! gpioset "${GPIO_INFO[0]}" "${GPIO_INFO[1]%$'\n'}"="$OUT_VAL"; then
-        echo " failed"
-        return 1
-    fi
-
-    echo " success"
-    return 0
-}
-
-set_fan()
-{
-    FAN_ID=$1
-    FAN_DUTY=$2
-    SYSFA_PWM_PATH=""
-
-    for file in /sys/devices/platform/pwm-fan"$FAN_ID"/hwmon/hwmon*/pwm1
-    do
-        if [ -e "$file" ]; then
-            SYSFA_PWM_PATH="$file"
-            break
-        fi
-    done
-
-    if [ -z "$SYSFA_PWM_PATH" ]; then
-        echo "set_fan: pwm file not found, chekc fan id ($FAN_ID)"
-        return 1
-    fi
-
-    if [ "$FAN_DUTY" -lt 0 ] || [ "$FAN_DUTY" -gt 100 ]; then
-        echo "set_fan: incorrect fan duty, $FAN_DUTY"
-        return 1
-    fi
-
-    # convert duty (0-100) to pwm value (0-255)
-    PWM_VAL=$(printf "%.0f" $((FAN_DUTY*255/100)))
-
-    echo -n "set_fan: set fan$FAN_ID = $FAN_DUTY"
-    if ! echo "$PWM_VAL" > "$SYSFA_PWM_PATH"; then
-        echo " failed"
-        return 1
-    fi
-
-    echo " success"
-    return 0
-}
+# shellcheck source=meta-facebook/meta-bletchley/recipes-bletchley/plat-tools/files/bletchley-common-functions
+source /usr/libexec/bletchley-common-functions
 
 # set initial value for GPIO output pins
 set_gpio SEL_SPI2_MUX       1