fsfmerge.sh: Assume current directory is GCC (instead of hard-coded path)

Change-Id: Iecd271f4f278d0e42f81ccfd36584bd95c79be40
diff --git a/fsfmerge.sh b/fsfmerge.sh
index dc9f1a4..89ae6cb 100755
--- a/fsfmerge.sh
+++ b/fsfmerge.sh
@@ -1,6 +1,6 @@
 #!/bin/bash
 
-export GIT_WORK_TREE=/work/sources/gcc.git
+export GIT_WORK_TREE=$(pwd)
 export GIT_DIR="$GIT_WORK_TREE"/.git
 
 NC='\e[0m'