main_help.c: Unchecked return value from library error spotted by Coverity

[Ryan Long]

CID 1437650: Unchecked return value from library in rtems_shell_help().

472        strcpy(priv->prefix, "/dev/gr740_0");
473        priv->prefix[11] += dev->minor_drv;
   CID 1437630 (#1 of 1): Unchecked return value from library (CHECKED_RETURN)2. check_return: Calling mkdir(priv->prefix, 511U) without checking return value. This library function may fail and return an error code. [Note: The source code implementation of the function has been overridden by a builtin model.]
474        mkdir(priv->prefix, S_IRWXU | S_IRWXG | S_IRWXO);
475        priv->prefix[12] = '/';
476        priv->prefix[13] = '\0';

[Ryan Long]

Accidentally put in the wrong reference to the error in the source.

121    if (lines && (line > lines)) {
   CID 1437650 (#2 of 2): Unchecked return value from library (CHECKED_RETURN)7. check_return: Calling getchar() without checking return value. This library function may fail and return an error code.
122      printf("Press any key to continue...");getchar();
123      printf("\n");

[Ryan Long <ryan.long@…>]

In fbab832/rtems:

main_help.c: Unchecked return value from library (CID #1437650)

CID 1437650: Unchecked return value from library in rtems_shell_help().

Closes #4291

[Ryan Long]

Another issue was found at line 150 after submitting the first patch

150        printf("Press any key to continue...");
   CID 1437650 (#1 of 1): Unchecked return value from library (CHECKED_RETURN)29. check_return: Calling getchar() without checking return value. This library function may fail and return an error code.
151        getchar();

[Ryan Long <ryan.long@…>]

In 2deba02/rtems:

main_help.c: Do not care what char is returned by getchar()

CID 1437650: Unchecked return value from library in rtems_shell_help().

Closes #4291