gnu: Add htslib-1.9.

* gnu/packages/bioinformatics.scm (htslib-1.9): New variable.

gnu/packages/bioinformatics.scm

@@ -4250,6 +4250,19 @@ (define-public htslib
     ;; the rest is released under the Expat license
     (license (list license:expat license:bsd-3))))
 
+(define-public htslib-1.9
+  (package (inherit htslib)
+    (name "htslib")
+    (version "1.9")
+    (source (origin
+              (method url-fetch)
+              (uri (string-append
+                    "https://github.com/samtools/htslib/releases/download/"
+                    version "/htslib-" version ".tar.bz2"))
+              (sha256
+               (base32
+                "16ljv43sc3fxmv63w7b2ff8m1s7h89xhazwmbm1bicz8axq8fjz0"))))))
+
 ;; This package should be removed once no packages rely upon it.
 (define htslib-1.3
   (package