DM/HV: Increase VM name len

VM Name length is restricted to 32 characters. kata creates
a VM name with GUID added as a part of VM name making it around
80 characters. So increasing this size to 128.

v1->v2:
It turns out that MAX_VM_OS_NAME_LEN usage in DM and HV are for
different use cases. So removing the macro from acrn_common.h.
Definied macro MAX_VMNAME_LEN for DM purposes in dm.h. Retaining
original macron name MAX_VM_OS_NAME_LEN for HV purposes but defined
in vm_config.h.

Tracked-On: #3138
Signed-off-by: Vijay Dhanraj <vijay.dhanraj@intel.com>
Acked-by: Anthony Xu <anthony.xu@intel.com>

devicemodel/include/dm.h

@@ -34,6 +34,8 @@
 #include "vmm.h"
 #include "dm_string.h"
 
+#define MAX_VMNAME_LEN	128U
+
 struct vmctx;
 extern int guest_ncpus;
 extern char *guest_uuid_str;