ucm: add integer comparison condition (Syntax 9)

Adds support for integer comparison operations in If.Condition blocks.
Supports operators: ==, !=, <, >, <=, >= for comparing integer values.
Both values are substituted and converted from strings to 64-bit integers.
Hexadecimal (C like) strings are also accepted (like 0x1234).

Example usage:
  If.check_channels {
    Condition {
      Type Integer
      Operation ">"
      Value1 "${var:channels}"
      Value2 "2"
    }
    True { ... }
  }

Signed-off-by: Jaroslav Kysela <perex@perex.cz>

src/ucm/ucm_confdoc.h

@@ -878,6 +878,32 @@ If.fmic {
 }
 ~~~
 
+#### Integer comparison (Type Integer)
+
+Field                | Description
+---------------------|-----------------------
+Operation            | comparison operator (==, !=, <, >, <=, >=)
+Value1               | first integer value (string converted to long long)
+Value2               | second integer value (string converted to long long)
+
+Note: Integer condition is supported in *Syntax* version *9*+.
+
+Example:
+
+~~~{.html}
+If.check_channels {
+  Condition {
+    Type Integer
+    Operation ">"
+    Value1 "${var:channels}"
+    Value2 "2"
+  }
+  True {
+    ...
+  }
+}
+~~~
+
 ### Variants
 
 To avoid duplication of the many configuration files for the cases with