Clarify default return for INFO_IL in spec.

Author: aarongreig

include/ur_api.h

@@ -4483,7 +4483,8 @@ typedef enum ur_program_info_t {
                                          ///< This is either the list of devices associated with the context or a
                                          ///< subset of those devices when the program is created using ::urProgramCreateWithBinary.
     UR_PROGRAM_INFO_IL = 4,              ///< [char[]] Return program IL if the program was created with
-                                         ///< ::urProgramCreateWithIL
+                                         ///< ::urProgramCreateWithIL, otherwise return size will be set to 0 and
+                                         ///< nothing will be returned.
     UR_PROGRAM_INFO_BINARY_SIZES = 5,    ///< [size_t[]] Return program binary sizes for each device.
     UR_PROGRAM_INFO_BINARIES = 6,        ///< [unsigned char[]] Return program binaries for all devices for this
                                          ///< Program.

scripts/core/program.yml

@@ -377,7 +377,7 @@ etors:
           [$x_device_handle_t[]] Return list of devices associated with a program.
           This is either the list of devices associated with the context or a subset of those devices when the program is created using $xProgramCreateWithBinary.
     - name: IL
-      desc: "[char[]] Return program IL if the program was created with $xProgramCreateWithIL"
+      desc: "[char[]] Return program IL if the program was created with $xProgramCreateWithIL, otherwise return size will be set to 0 and nothing will be returned."
     - name: BINARY_SIZES
       desc: "[size_t[]] Return program binary sizes for each device."
     - name: BINARIES