trace-events: Fix the name of the tracing.rst file

The file has been converted to .rst a while ago - make sure that the
references in the trace-events files are pointing to the right location
now.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>

bsd-user/trace-events

@@ -1,4 +1,4 @@
-# See docs/tracing.txt for syntax documentation.
+# See docs/devel/tracing.rst for syntax documentation.
 
 # bsd-user/signal.c
 user_setup_frame(void *env, uint64_t frame_addr) "env=%p frame_addr=0x%"PRIx64

ebpf/trace-events

@@ -1,4 +1,4 @@
-# See docs/devel/tracing.txt for syntax documentation.
+# See docs/devel/tracing.rst for syntax documentation.
 
 # ebpf-rss.c
 ebpf_error(const char *s1, const char *s2) "error in %s: %s"

hw/nubus/trace-events

@@ -1,4 +1,4 @@
-# See docs/devel/tracing.txt for syntax documentation.
+# See docs/devel/tracing.rst for syntax documentation.
 
 # nubus-bus.c
 nubus_slot_read(uint64_t addr, int size) "reading unassigned addr 0x%"PRIx64 " size %d"

target/s390x/kvm/trace-events

@@ -1,4 +1,4 @@
-# See docs/devel/tracing.txt for syntax documentation.
+# See docs/devel/tracing.rst for syntax documentation.
 
 # kvm.c
 kvm_enable_cmma(int rc) "CMMA: enabling with result code %d"