Fix compiling for SPARC_SE:

- change include from exec_context.hh -> threadcontext.hh
- g++ 4.0.3 complaint about broken code (which it was).
- bad merge thread_context -> exec_context

src/arch/sparc/isa/includes.isa:
    Fix SPARC_SE for exec_context->thread_context switch
src/arch/sparc/regfile.hh:
    fix g++ 4.0.3 complaint about broken code (which it was).
src/cpu/thread_context.hh:
    fix bad merge

--HG--
extra : convert_revision : f5bab822d5c25177756e9890e143b0ad8d704201

src/cpu/thread_context.hh

@@ -245,6 +245,7 @@ class ThreadContext
 
     virtual void setSyscallReturn(SyscallReturn return_value) = 0;
 
+    virtual void syscall(int64_t callnum) = 0;
 
     // Same with st cond failures.
     virtual Counter readFuncExeInst() = 0;
@@ -431,6 +432,7 @@ class ProxyThreadContext : public ThreadContext
     void setSyscallReturn(SyscallReturn return_value)
     { actualTC->setSyscallReturn(return_value); }
 
+    void syscall(int64_t callnum) { actualTC->syscall(callnum); }
 
     Counter readFuncExeInst() { return actualTC->readFuncExeInst(); }
 #endif