Revert BUFF_SIZE fix, to be fixed in another PR. Add missing property entries

Author: linlingao

features/cellular/framework/AT/ATHandler.h

@@ -48,7 +48,7 @@ class FileHandle;
 extern const char *OK;
 extern const char *CRLF;
 
-#define BUFF_SIZE 128
+#define BUFF_SIZE 32
 
 /* AT Error types enumeration */
 enum DeviceErrorType {

features/cellular/framework/targets/GENERIC/GENERIC_AT3GPP/GENERIC_AT3GPP.cpp

@@ -37,6 +37,7 @@ static const intptr_t cellular_properties[AT_CellularDevice::PROPERTY_MAX] = {
     1,  // PROPERTY_IPV4V6_STACK
     0,  // PROPERTY_NON_IP_PDP_TYPE
     1,  // PROPERTY_AT_CGEREP
+    1,  // PROPERTY_AT_COPS_FALLBACK_AUTO
 };
 
 GENERIC_AT3GPP::GENERIC_AT3GPP(FileHandle *fh) : AT_CellularDevice(fh)

features/cellular/framework/targets/MultiTech/DragonflyNano/PPP/SARA4_PPP.cpp

@@ -37,6 +37,7 @@ static const intptr_t cellular_properties[AT_CellularDevice::PROPERTY_MAX] = {
     0,  // PROPERTY_IPV4V6_STACK
     0,  // PROPERTY_NON_IP_PDP_TYPE
     1,  // PROPERTY_AT_CGEREP
+    1,  // PROPERTY_AT_COPS_FALLBACK_AUTO
 };
 
 SARA4_PPP::SARA4_PPP(FileHandle *fh) : AT_CellularDevice(fh)