Remove: ARM_MUSCA_A1 support

ARM_MUSCA_A1 is not supported since Mbed Os 6.0
ARMmbed#13165

Therefore remove files.

Author: jainvikas8

storage/kvstore/kv_config/global/mbed_lib.json

@@ -38,9 +38,6 @@
         "LPC55S69_S": {
             "storage_type": "TDB_INTERNAL"
         },
-        "ARM_MUSCA_A1_S": {
-            "storage_type": "TDB_INTERNAL"
-        },
         "ARM_MUSCA_B1_S": {
             "storage_type": "TDB_INTERNAL"
         },

storage/kvstore/kv_config/tdb_internal/mbed_lib.json

@@ -23,10 +23,6 @@
             "internal_size": "2*FLASH_SECTOR_SIZE",
             "internal_base_address": "0x080C0000"
         },
-        "ARM_MUSCA_A1_S": {
-            "internal_size": "0x8000",
-            "internal_base_address": "0x00420000"
-        },
        "ARM_MUSCA_B1_S": {
             "internal_size": "0x8000",
             "internal_base_address": "0x10000000"

tools/targets/ARM_MUSCA_A1.py

@@ -681,21 +681,6 @@ def sign_image(t_self, resources, elf, binf):
             psoc6_sign_image(t_self, resources, elf, binf, m0hexf)
 
 
-class ArmMuscaA1Code(object):
-    """Musca-A1 Hooks"""
-    @staticmethod
-    def binary_hook(t_self, resources, elf, binf):
-        from tools.targets.ARM_MUSCA_A1 import musca_tfm_bin
-        configured_secure_image_filename = t_self.target.secure_image_filename
-        secure_bin = find_secure_image(
-            t_self.notify,
-            resources,
-            binf,
-            configured_secure_image_filename,
-            FileType.BIN
-        )
-        musca_tfm_bin(t_self, binf, secure_bin)
-
 class ArmMuscaB1Code(object):
     """Musca-B1 Hooks"""
     @staticmethod