Remove PSA unnecesary label

Author: Chris Trowbridge

mbed_app.json

@@ -143,7 +143,7 @@
             "target.features_add"                       : ["LWIP", "STORAGE", "BOOTLOADER"],
             "target.features_remove"                    : ["BLE"],
             "target.extra_labels_remove"                : ["CORDIO", "CORDIO_LL", "NORDIC_CORDIO"],
-            "target.extra_labels_add"                   : ["SOFTDEVICE_NONE", "PSA"],
+            "target.extra_labels_add"                   : ["SOFTDEVICE_NONE"],
             "target.macros_add"                         : ["MBEDTLS_USER_CONFIG_FILE=\"mbedTLSConfig_mbedOS.h\"", "MBED_BOOTLOADER_ACTIVE_HEADER_REGION_SIZE=1024", "MBED_ROM_START=0x0"],
             "target.bootloader_img"                     : "bootloader/mbed-bootloader-ep-agora-block_device-kvstore-v4.0.2.hex",
             "target.header_offset"                      : "0xB000",