Fix DISCO_L475VG_IOT01A name at json

Author: Offir Kochalsky

components/storage/blockdevice/COMPONENT_QSPIF/mbed_lib.json

@@ -7,7 +7,7 @@
         "DISCO_F413ZH": {
              "QSPI_FREQ": "80000000"
         },
-       "DISCO_L475VG": {
+       "DISCO_L475VG_IOT01A": {
              "QSPI_FREQ": "8000000"
         },
        "DISCO_L476VG": {