Fix some typos

Author: ngzhian

document/core/binary/instructions.rst

@@ -667,7 +667,7 @@ All other SIMD instructions are plain opcodes without any immediates.
    \begin{array}{llclll}
    \phantom{\production{instruction}} & \phantom{\Binstr} &\phantom{::=}& \phantom{\dots} && \phantom{simdhaslongerinstructionnames} \\[-2ex] &&|&
      \hex{FD}~~193{:}\Bu32 &\Rightarrow& \I64X2.\VNEG \\ &&|&
-     \hex{FD}~~196{:}\Bu32 &\Rightarrow& \I64x2.\BITMASK \\ &&|&
+     \hex{FD}~~196{:}\Bu32 &\Rightarrow& \I64X2.\BITMASK \\ &&|&
      \hex{FD}~~203{:}\Bu32 &\Rightarrow& \I64X2.\VSHL \\ &&|&
      \hex{FD}~~204{:}\Bu32 &\Rightarrow& \I64X2.\VSHR\K{\_s} \\ &&|&
      \hex{FD}~~205{:}\Bu32 &\Rightarrow& \I64X2.\VSHR\K{\_u} \\ &&|&

document/core/text/instructions.rst

@@ -701,7 +701,7 @@ SIMD const instructions have a mandatory :ref:`shape <syntax-simd-shape>` descri
    \begin{array}{llclll}
    \phantom{\production{instruction}} & \phantom{\Tplaininstr_I} &\phantom{::=}& \phantom{averylonginstructionnameforsimdtext} && \phantom{simdhasreallylonginstructionnames} \\[-2ex] &&|&
      \text{i64x2.neg} &\Rightarrow& \I64X2.\VNEG\\ &&|&
-     \text{i64x2.bitmask} &\Rightarrow& \I64x2.\BITMASK\\ &&|&
+     \text{i64x2.bitmask} &\Rightarrow& \I64X2.\BITMASK\\ &&|&
      \text{i64x2.shl} &\Rightarrow& \I64X2.\VSHL\\ &&|&
      \text{i64x2.shr\_s} &\Rightarrow& \I64X2.\VSHR\K{\_s}\\ &&|&
      \text{i64x2.shr\_u} &\Rightarrow& \I64X2.\VSHR\K{\_u}\\ &&|&