Fix list item in grdmath.rst (#8596)

Notes on functions requiring positive inputs and bitwise operators were combined in a single item of the list.

doc/rst/source/grdmath.rst

@@ -518,14 +518,16 @@ Notes On Operators
 #. The stack depth limit is hard-wired to 100.
 
 #. All functions expecting a positive radius (e.g., **LOG**, **KEI**,
-   etc.) are passed the absolute value of their argument. (9) The bitwise
-   operators (**BITAND**, **BITLEFT**, **BITNOT**, **BITOR**, **BITRIGHT**,
-   **BITTEST**, and **BITXOR**) convert a grid's single precision values to
-   unsigned 32-bit ints to perform the bitwise operations. Consequently,
-   the largest whole integer value that can be stored in a float grid is
-   2^24 or 16,777,216. Any higher result will be masked to fit in the lower
-   24 bits.  Thus, bit operations are effectively limited to 24 bit.  All
-   bitwise operators return NaN if given NaN arguments or bit-settings <= 0.
+   etc.) are passed the absolute value of their argument. 
+
+#. The bitwise operators (**BITAND**, **BITLEFT**, **BITNOT**, **BITOR**,
+   **BITRIGHT**, **BITTEST**, and **BITXOR**) convert a grid's single
+   precision values to unsigned 32-bit ints to perform the bitwise
+   operations. Consequently, the largest whole integer value that can be
+   stored in a float grid is 2^24 or 16,777,216. Any higher result will be
+   masked to fit in the lower 24 bits. Thus, bit operations are effectively
+   limited to 24 bit. All bitwise operators return NaN if given NaN
+   arguments or bit-settings <= 0.
 
 #. When OpenMP support is compiled in, a few operators will take advantage
    of the ability to spread the load onto several cores.  At present, the