Remove libcurl and libexpat dependencies

INSTALL.md

@@ -2,18 +2,16 @@
 
 ## System Requirements and Dependencies
 
-The distributed binaries require the readline or libedit, curl, expat,
-and zlib libraries to be installed.
+The distributed binaries require the readline or libedit, and zlib
+libraries to be installed.
 
 On Debian and its derivatives (Ubuntu, Mint, Devuan, Raspbian etc.):
 
-	$ sudo apt install gcc make bison flex zlib1g-dev
-	$ sudo apt install libcurl4-openssl-dev libexpat-dev libreadline-dev
+	$ sudo apt install gcc make bison flex zlib1g-dev libreadline-dev
 
 On Fedora and its derivatives (Redhat, Scientific Linux etc.)
 
-	$ sudo dnf install gcc make perl flex bison zlib-devel
-	$ sudo dnf install libcurl-devel expat-devel readline-devel
+	$ sudo dnf install gcc make perl flex bison zlib-devel readline-devel
 
 On macOS, you need to have the XCode tools installed. If you
 haven't, you can install them with:

unix/boot/spp/xc.c

@@ -72,8 +72,6 @@ char *iraflibs[] = { "libex.a",
 
 char *fortlib[] = { "-lf2c",
 		    "-lm",
-		    "-lcurl",
-		    "-lexpat",
 #if (defined (__linux__) || defined (__gnu_hurd__))
 		    "-lpthread",
 #endif