arm: Fix typo in ldrsh instruction name

ldrsh was typoed as hdrsh, which is a bit annoying when printing
instructions.  This patch fixes it.
diff --git a/src/arch/arm/isa/insts/ldr.isa b/src/arch/arm/isa/insts/ldr.isa
index 6bfe401..3edeb38 100644
--- a/src/arch/arm/isa/insts/ldr.isa
+++ b/src/arch/arm/isa/insts/ldr.isa
@@ -349,7 +349,7 @@
     buildLoads("ldrsbt", size=1, sign=True, user=True)
     buildLoads("ldrh", size=2)
     buildLoads("ldrht", size=2, user=True)
-    buildLoads("hdrsh", size=2, sign=True)
+    buildLoads("ldrsh", size=2, sign=True)
     buildLoads("ldrsht", size=2, sign=True, user=True)
 
     buildDoubleLoads("ldrd")