Rename "RTL" to "bytecode"

"RTL" didn't make any sense, and now that there's no other bytecode to
disambiguate against, just call it bytecode.

* module/Makefile.am:
* module/ice-9/eval-string.scm:
* module/language/bytecode.scm:
* module/language/bytecode/spec.scm:
* module/language/cps/arities.scm:
* module/language/cps/compile-bytecode.scm:
* module/language/cps/compile-rtl.scm:
* module/language/cps/contification.scm:
* module/language/cps/elide-values.scm:
* module/language/cps/primitives.scm:
* module/language/cps/reify-primitives.scm:
* module/language/cps/spec.scm:
* module/language/cps/specialize-primcalls.scm:
* module/language/rtl.scm:
* module/language/rtl/spec.scm:
* module/scripts/compile.scm:
* module/system/base/compile.scm:
* module/system/repl/common.scm:
* module/system/vm/assembler.scm:
* module/system/vm/debug.scm:
* module/system/vm/disassembler.scm:
* module/system/vm/dwarf.scm:
* test-suite/tests/cross-compilation.test:
* test-suite/tests/dwarf.test:
* test-suite/tests/rtl-compilation.test:
* test-suite/tests/rtl.test:
* test-suite/vm/run-vm-tests.scm: Fixups.

module/scripts/compile.scm

@@ -139,7 +139,7 @@ There is NO WARRANTY, to the extent permitted by law.~%"))
                                 (cons #:O o)
                                 o)))
          (from            (or (assoc-ref options 'from) 'scheme))
-         (to              (or (assoc-ref options 'to) 'rtl))
+         (to              (or (assoc-ref options 'to) 'bytecode))
          (target          (or (assoc-ref options 'target) %host-type))
 	 (input-files     (assoc-ref options 'input-files))
 	 (output-file     (assoc-ref options 'output-file))
@@ -158,7 +158,7 @@ Compile each Guile source file FILE into a Guile object.
                        for a list of available warnings
 
   -f, --from=LANG      specify a source language other than `scheme'
-  -t, --to=LANG        specify a target language other than `rtl'
+  -t, --to=LANG        specify a target language other than `bytecode'
   -T, --target=TRIPLET produce bytecode for host TRIPLET
 
 Note that auto-compilation will be turned off.