[CodeGen] Print "%vreg0" as "%0" in both MIR and debug output

As part of the unification of the debug format and the MIR format, avoid
printing "vreg" for virtual registers (which is one of the current MIR
possibilities).

Basically:

* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E "s/%vreg([0-9]+)/%\1/g"
* grep -nr '%vreg' . and fix if needed
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E "s/ vreg([0-9]+)/ %\1/g"
* grep -nr 'vreg[0-9]\+' . and fix if needed

Differential Revision: https://reviews.llvm.org/D40420

llvm-svn: 319427
diff --git a/llvm/test/CodeGen/AVR/select-must-add-unconditional-jump.ll b/llvm/test/CodeGen/AVR/select-must-add-unconditional-jump.ll
index e6344df..64faff7 100644
--- a/llvm/test/CodeGen/AVR/select-must-add-unconditional-jump.ll
+++ b/llvm/test/CodeGen/AVR/select-must-add-unconditional-jump.ll
@@ -11,10 +11,10 @@
 ;
 ; BB#2: derived from LLVM BB %finish
 ;     Predecessors according to CFG: BB#0 BB#1
-;         %vreg0<def> = PHI %vreg3, <BB#0>, %vreg5, <BB#1>
-;         %vreg7<def> = LDIRdK 2
-;         %vreg8<def> = LDIRdK 1
-;         CPRdRr %vreg2, %vreg0, %SREG<imp-def>
+;         %0<def> = PHI %3, <BB#0>, %5, <BB#1>
+;         %7<def> = LDIRdK 2
+;         %8<def> = LDIRdK 1
+;         CPRdRr %2, %0, %SREG<imp-def>
 ;         BREQk <BB#6>, %SREG<imp-use>
 ;     Successors according to CFG: BB#5(?%) BB#6(?%)
 ;