sim,sim-se: Fixes the bug of missing "/" in path resolution

The syscall emulation did not correctly handle the scenario where the
base path does not end with "/". The "/" should be appended first
before the file name is appended. This commit fixes this bug.

Change-Id: I9a9b38d1885e46b2a0e42018fd7d68010c70133c
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/64471
Maintainer: Bobby Bruce <bbruce@ucdavis.edu>
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Bobby Bruce <bbruce@ucdavis.edu>

src/sim/process.cc

@@ -520,7 +520,7 @@ Process::absolutePath(const std::string &filename, bool host_filesystem)
     }
 
     // Add a trailing '/' if the current working directory did not have one.
-    normalize(path_base);
+    path_base = normalize(path_base);
 
     // Append the filename onto the current working path.
     auto absolute_path = path_base + filename;