compilation warning -Wdouble-promotion on samples/sensor/lsm6dsl

[FRASTM]

Describe the bug
Building the samples/sensor/lsm6dsl on an existing board like the disco_l475_iot1 gives the following warning messages :

warning: implicit conversion from 'float' to 'double' when passing argument to function [-Wdouble-promotion]
  157 |                                                            out_ev(&gyro_x_out),

To Reproduce
Steps to reproduce the behavior:

1. west build -p auto -b disco_l475_iot1 samples/sensor/lsm6dsl

Expected behavior
no compilation warning

Impact
CI and twister testing failed

[Check failure on line 0 in disco_l475_iot1:samples/sensor/lsm6dsl/sample.sensor.lsm6dsl](https://github.com/zephyrproject-rtos/zephyr/pull/68274/files#annotation_17442858300)

@github-actions github-actions / Unit Test Results

samples/sensor/lsm6dsl/sample.sensor.lsm6dsl (disco_l475_iot1:samples/sensor/lsm6dsl/sample.sensor.lsm6dsl) with error

artifacts/Unit Test Results (Subset 5)/twister-out/twister.xml [took 0s]

Environment (please complete the following information):

• OS: ubuntu
• Toolchain (e.g Zephyr SDK, ...) 0.16.3
• Commit SHA or Version used 6a41a7a

Additional context
warning message raised due to
--> commit 018dbcf from #57154