rtla: Minor grammar fix for rtla README

- Change to "The rtla meta-tool includes"
- Remove an unnecessary "But, "
- Adjust the formatting of the paragraph resulting from the changes.
- Simplify the wording for the libraries and tools.

Link: https://lkml.kernel.org/r/437f0accdde53713ab3cce46f3564be00487e031.1651247710.git.bristot@kernel.org
Link: https://lore.kernel.org/r/20220408161012.10544-1-jkacur@redhat.com/

Cc: Daniel Bristot de Oliveria <bristot@kernel.org>
Fixes: 79ce8f43 ("rtla: Real-Time Linux Analysis tool")
Acked-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: John Kacur <jkacur@redhat.com>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>

tools/tracing/rtla/README.txt

 RTLA: Real-Time Linux Analysis tools
 
-The rtla is a meta-tool that includes a set of commands that
-aims to analyze the real-time properties of Linux. But, instead of
-testing Linux as a black box, rtla leverages kernel tracing
-capabilities to provide precise information about the properties
-and root causes of unexpected results.
+The rtla meta-tool includes a set of commands that aims to analyze
+the real-time properties of Linux. Instead of testing Linux as a black box,
+rtla leverages kernel tracing capabilities to provide precise information
+about the properties and root causes of unexpected results.
 
 Installing RTLA
 
-RTLA depends on some libraries and tools. More precisely, it depends on the
-following libraries:
+RTLA depends on the following libraries and tools:
 
  - libtracefs
  - libtraceevent