Reoptimize LUT-based Sigmoid evaluation stubs

Recalculate tables to remove masking of extracted exponent bits

PiperOrigin-RevId: 333661363
diff --git a/CMakeLists.txt b/CMakeLists.txt
index fb532e3..b9cf242 100755
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -233,7 +233,9 @@
 
 SET(XNNPACK_TABLE_SRCS
   src/tables/exp2-k-over-64.c
-  src/tables/exp2-k-over-2048.c)
+  src/tables/exp2-k-over-2048.c
+  src/tables/exp2minus-k-over-64.c
+  src/tables/exp2minus-k-over-2048.c)
 
 SET(XNNPACK_SCALAR_MICROKERNEL_SRCS
   src/f32-argmaxpool/4x-scalar-c1.c