tools/xl: Add altp2m_count parameter

Introduce a new altp2m_count parameter to control the maximum number of altp2m
views a domain can use. By default, if altp2m_count is unspecified and altp2m
is enabled, the value is set to 10, reflecting the legacy behavior.

This change is preparatory; it establishes the groundwork for the feature but
does not activate it.

Signed-off-by: Petr Beneš <w1benny@gmail.com>
Reviewed-by: Anthony PERARD <anthony.perard@vates.tech>
Acked-by: Nick Rosbrook <enr0n@ubuntu.com>

tools/xl/xl_parse.c

@@ -2099,6 +2099,15 @@ void parse_config_data(const char *config_source,
         }
     }
 
+    if (!xlu_cfg_get_long(config, "altp2m_count", &l, 1)) {
+        if (l != (uint16_t)l) {
+            fprintf(stderr, "ERROR: invalid value %ld for \"altp2m_count\"\n", l);
+            exit (1);
+        }
+
+        b_info->altp2m_count = l;
+    }
+
     if (!xlu_cfg_get_long(config, "vmtrace_buf_kb", &l, 1) && l) {
         b_info->vmtrace_buf_kb = l;
     }