cmake: Sanitize NAME for _main symbol generation

Program names containing '-' (for example, renaming hello to
hello-world via PROGNAME) previously generated an invalid identifier
<NAME>_main when constructing the main= compiler definition and the
APP_MAIN target property used during builtin list generation. This
caused the CMake build to fail because '-' is not a valid character in
a C identifier.

This mirrors the Make-based fix (Application.mk's PROGSYM) for the
traditional build.

Introduce NAME_SYM, a sanitized copy of NAME with '-' replaced by '_',
and use it only where an internal C identifier is required: the
main= COMPILE_DEFINITIONS property and the APP_MAIN target property.
Leave NAME unchanged everywhere else, including CMake target/output
names and the APP_NAME property, where hyphens are valid.

The standalone/loadable executable path (MODULE/DYNLIB/kernel build)
does not rename main() and therefore requires no sanitization because
each executable is linked independently rather than merged into a
shared builtin image.

Testing (WSL2 Ubuntu, x86_64):
- BOARD_CONFIG=sim/nsh, CONFIG_EXAMPLES_HELLO_PROGNAME="hello-world":
  clean CMake configure/build; 'hello-world' runs and prints
  'Hello, World!!'
- Reverted to CONFIG_EXAMPLES_HELLO_PROGNAME="hello": reconfigured
  and rebuilt; 'hello' runs and prints 'Hello, World!!' (no
  regression)

Fixes #19447

Signed-off-by: Ansh Rai <anshrai331@gmail.com>

cmake/nuttx_add_application.cmake

@@ -111,6 +111,8 @@ function(nuttx_add_application)
     return()
   endif()
 
+  string(REPLACE "-" "_" NAME_SYM "${NAME}")
+
   # check if SRCS exist
   if(SRCS)
     file(GLOB SRCS_EXIST ${SRCS})
@@ -257,7 +259,7 @@ function(nuttx_add_application)
         set_property(
           SOURCE ${MAIN_SRC}
           APPEND
-          PROPERTY COMPILE_DEFINITIONS main=${NAME}_main)
+          PROPERTY COMPILE_DEFINITIONS main=${NAME_SYM}_main)
       endif()
     endif()
 
@@ -275,7 +277,7 @@ function(nuttx_add_application)
 
   # store parameters into properties (used during builtin list generation)
 
-  set_target_properties(${TARGET} PROPERTIES APP_MAIN ${NAME}_main)
+  set_target_properties(${TARGET} PROPERTIES APP_MAIN ${NAME_SYM}_main)
   set_target_properties(${TARGET} PROPERTIES APP_NAME ${NAME})
 
   if(PRIORITY)