README.md:  add perl-FindBin to Fedora prereqs

Issue #3798 pointed out perl-FindBin is required on Fedora 34 to
configure and build openssl.

Change-Id: I0966fc7992cbc192eef5b156546565ea90c73cab
Signed-off-by: Milton Miller <miltonm@us.ibm.com>
diff --git a/README.md b/README.md
index 437d3d4..f888b3c 100644
--- a/README.md
+++ b/README.md
@@ -24,7 +24,7 @@
 
 ```
 sudo dnf install -y git patch diffstat texinfo chrpath SDL-devel bitbake \
-    rpcgen perl-Thread-Queue perl-bignum perl-Crypt-OpenSSL-Bignum
+    rpcgen perl-Thread-Queue perl-bignum perl-Crypt-OpenSSL-Bignum perl-FindBin
 sudo dnf groupinstall "C Development Tools and Libraries"
 ```
 ### 2) Download the source