Add reset internal state before call to HAL_QspiInit function

[adustm]

Description

This PR fixes an issue we noticed with @maciejbocianski during qspi_tests validation for ARM toolchain. (refer #7325)

2 variables in STM QSPI handle structure shall be initialized before the 1st call to HAL_QSPIInit function (at least the 1st call after the object creation)

hqspi->State shall be = HAL_QSPI_STATE_RESET
and hqspi->Lock shall be =HAL_UNLOCK

If the qspi object is created on the stack, it won't be zero-initialized and we don't know in advance the value of those 2 variables

With this PR, ARM test is passing

+-------------------------+---------------------+---------------------+--------+--------------------+-------------+
| target                  | platform_name       | test suite          | result | elapsed_time (sec) | copy_method |
+-------------------------+---------------------+---------------------+--------+--------------------+-------------+
| DISCO_L475VG_IOT01A-ARM | DISCO_L475VG_IOT01A | tests-mbed_hal-qspi | OK     | 41.5               | default     |
+-------------------------+---------------------+---------------------+--------+--------------------+-------------+

Pull request type

[x] Fix
[ ] Refactor
[ ] New target
[ ] Feature
[ ] Breaking change

[0xc0170]

/morph build

[mbed-ci]

Build : SUCCESS

Build number : 2662
Build artifacts/logs : http://mbed-os.s3-website-eu-west-1.amazonaws.com/?prefix=builds/7586/

Triggering tests

/morph test
/morph uvisor-test
/morph export-build
/morph mbed2-build

[mbed-ci]

Test : SUCCESS

Build number : 2403
Test logs :http://mbed-os-logs.s3-website-us-west-1.amazonaws.com/?prefix=logs/7586/2403

[mbed-ci]

Exporter Build : SUCCESS

Build number : 2295
Build artifacts/logs : http://mbed-os.s3-website-eu-west-1.amazonaws.com/?prefix=builds/exporter/7586/