scons: Don't accumulate SLICC_INCLUDES.

Presumably, these are fixed for whatever protocol that gets selected. We
don't need to accumulate includes, we need to set includes to something
in particular. If there is a common include which always needs to be
used, we can handle that in the SConscript separately from
SLICC_INCLUDES.

Change-Id: I996d08566944e38e388dc287f644c40366ebba0d
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/56754
Tested-by: kokoro <noreply+kokoro@google.com>
Maintainer: Gabe Black <gabe.black@gmail.com>
Reviewed-by: Yu-hsin Wang <yuhsingw@google.com>

src/mem/ruby/protocol/SConscript

@@ -60,13 +60,15 @@ slicc_scanner = Classic("SliccScanner", ['.sm', '.slicc'], "SLICC_PATH",
                         r'''include[ \t]["'](.*)["'];''')
 env.Append(SCANNERS=slicc_scanner)
 
+slicc_includes = ['mem/ruby/slicc_interface/RubySlicc_includes.hh'] + \
+        env['SLICC_INCLUDES']
 def slicc_emitter(target, source, env):
     assert len(source) == 1
     filepath = source[0].srcnode().abspath
 
     slicc = SLICC(filepath, protocol_base.abspath, verbose=False)
     slicc.process()
-    slicc.writeCodeFiles(output_dir.abspath, env['SLICC_INCLUDES'])
+    slicc.writeCodeFiles(output_dir.abspath, slicc_includes)
     if env['SLICC_HTML']:
         slicc.writeHTMLFiles(html_dir.abspath)
 
@@ -79,7 +81,7 @@ def slicc_action(target, source, env):
 
     slicc = SLICC(filepath, protocol_base.abspath, verbose=True)
     slicc.process()
-    slicc.writeCodeFiles(output_dir.abspath, env['SLICC_INCLUDES'])
+    slicc.writeCodeFiles(output_dir.abspath, slicc_includes)
     if env['SLICC_HTML']:
         slicc.writeHTMLFiles(html_dir.abspath)
 

src/mem/ruby/protocol/SConsopts

@@ -51,5 +51,3 @@ main.Append(PROTOCOL_DIRS=[Dir('.')])
 
 protocol_base = Dir('.')
 Export('protocol_base')
-
-main.Append(SLICC_INCLUDES=['mem/ruby/slicc_interface/RubySlicc_includes.hh'])