chore(driver/bpf): fix warning in bpf_accumulate_argv_or_env

Recent versions of clang tend to emit the following warning:

In file included from /usr/src/draios-agent-14.2.4/bpf/probe.c:26:
/usr/src/draios-agent-14.2.4/bpf/fillers.h:2311:48: warning: passing 'volatile long *' to parameter of type 'long *' discards qualifiers [-Wincompatible-pointer-types-discards-qualifiers]
 2311 |                 res = bpf_accumulate_argv_or_env(data, argv, &args_len);
      |                                                              ^~~~~~~~~
/usr/src/draios-agent-14.2.4/bpf/fillers.h:1921:61: note: passing argument to parameter 'args_len' here
 1921 |                                                       long *args_len) {
      |                                                             ^

Jut make the (other) variable and the argument volatile.

Signed-off-by: Gerlando Falauto <[email protected]>

Author: iurly

driver/bpf/fillers.h

@@ -1954,7 +1954,7 @@ static __always_inline int bpf_append_cgroup(struct task_struct *task, char *buf
 
 static __always_inline int bpf_accumulate_argv_or_env(struct filler_data *data,
                                                       char **argv,
-                                                      long *args_len) {
+                                                      volatile long *args_len) {
 	char *arg;
 	int off;
 	int len;
@@ -2616,7 +2616,7 @@ FILLER(proc_startupdate_3, true) {
 		/*
 		 * execve family parameters.
 		 */
-		long env_len = 0;
+		volatile long env_len = 0;
 		kuid_t loginuid;
 		uint32_t tty;
 		struct file *exe_file;