Addition of subject Computer Organization and Architecture (#5706)

* Update free-programming-books-subjects.md

* Update free-programming-books-subjects.md

* Update free-programming-books-subjects.md

* Update free-programming-books-subjects.md

* Update free-programming-books-subjects.md

* Update free-programming-books-subjects.md

* Added a book under Computer Organization

Hey, I added one more free book under the subject. It's a pretty broad category and I am sure more free books exist on the topic. I personally studied from the book by Smruti Sarang and felt that it's too precious a resource to not share. I think COA deserves a separate category not only because it is a college course but also because COA gives a first introduction to the implementation of digital systems inside computers (boolean algebra, latches, mux, registers) before focusing on Assembly languages like x86 and ARM. I skimmed through your misc list but since the subject doesn't focus on programming languages hence we cannot add the existing books like 'Scientific Programming and Computer Architecture' in it.

books/free-programming-books-subjects.md

@@ -14,6 +14,7 @@ Books that cover a specific programming language can be found in the  [BY PROGRA
 * [Cloud Computing](#cloud-computing)
 * [Competitive Programming](#competitive-programming)
 * [Compiler Design](#compiler-design)
+* [Computer Organization and Architecture](#computer-organization-and-architecture)
 * [Computer Science](#computer-science)
 * [Computer Vision](#computer-vision)
 * [Containers](#containers)
@@ -195,6 +196,12 @@ Books that cover a specific programming language can be found in the  [BY PROGRA
 * [The ANTLR Mega Tutorial](https://tomassetti.me/antlr-mega-tutorial/)
 
 
+### Computer Organization and Architecture
+
+* [Basic Computer Architecture](https://www.cse.iitd.ac.in/~srsarangi/archbooksoft.html) - Smruti R. Sarangi (HTML, PDF, Slides, Videos)
+* [Computer Organization and Design Fundamentals](https://faculty.etsu.edu/tarnoff/138292) - David Tarnoff (PDF)
+
+
 ### Computer Science
 
 * [Computational Thinking](https://www.cs.cmu.edu/~15110-s13/Wing06-ct.pdf) - Jeannette Wing, Carnegie-Mellon University (PDF)