man: fix required kernel version in man pages

Several man pages state that Linux 4.5 is required because the tool
relies on the bpf_perf_event_output helper.  However,
bpf_perf_event_output was introduced in Linux 4.4.

In addition, mountsnoop requires Linux 4.8 because it now uses
the bpf_get_current_task helper.

Signed-off-by: Paul Chaignon <[email protected]>
diff --git a/man/man8/bashreadline.8 b/man/man8/bashreadline.8
index 185598a..bc68a49 100644
--- a/man/man8/bashreadline.8
+++ b/man/man8/bashreadline.8
@@ -10,8 +10,8 @@
 
 This program is also a basic example of eBPF/bcc and uprobes.
 
-This makes use of a Linux 4.5 feature (bpf_perf_event_output()); 
-for kernels older than 4.5, see the version under tools/old,
+This makes use of a Linux 4.4 feature (bpf_perf_event_output());
+for kernels older than 4.4, see the version under tools/old,
 which uses an older mechanism
 
 Since this uses BPF, only the root user can use this tool.