[Buildroot] package/chawan: new package

[dowan gullient]

Hello Waldemar Brodkorb, thanks for your patch.

> +CHAWAN_LICENSE = Public Domain
The license identifier "Public Domain" is not a valid SPDX identifier. The
presence of an `UNLICENSE` file (listed in `CHAWAN_LICENSE_FILES` and 
present
in the `.hash` file) indicates the project uses the Unlicense. You must use
the valid SPDX identifier `Unlicense` instead. - [Source: Expert Intuition]

> +CHAWAN_DEPENDENCIES = host-nim brotli libssh2 openssl
The `CHAWAN_DEPENDENCIES` list is not sorted alphabetically. The correct
order is: `brotli`, `host-nim`, `libssh2`, `openssl`. - [Source: Expert 
Intuition]

> comment "chawan needs a toolchain w/ gcc >= 11"
>      depends on !BR2_TOOLCHAIN_GCC_AT_LEAST_11
The comment for the toolchain dependency should repeat all non-toolchain
dependencies of the package so that it is only visible when the package 
itself
would be visible. Since `chawan` also depends on `BR2_USE_MMU`, the comment
must depend on `BR2_USE_MMU` as well (e.g., `depends on BR2_USE_MMU &&
!BR2_TOOLCHAIN_GCC_AT_LEAST_11`). - [Source: Expert Intuition]

> TARGET_CONFIGURE_OPTS += \
>              FLAGS="--os=linux \
>              --cpu:$(CHAWAN_TARGET_ARCH) \
>              --gcc.exe:$(TARGET_CROSS)gcc \
>              --gcc.linkerexe:$(TARGET_CROSS)gcc" \
>              PREFIX="/usr"
When a variable assignment is split across multiple lines using a backslash,
all follow-up lines must be indented with exactly one single tab character.
The continuation lines here appear to use multiple tabs (or spaces). Please
adjust to a single tab per continuation line. - [Source: Expert Intuition]

> define CHAWAN_INSTALL_TARGET_CMDS
>      $(MAKE) $(TARGET_CONFIGURE_OPTS) -C $(@D) \
>          DESTDIR=$(TARGET_DIR) install
> endef
Inside a `define` block, command continuation lines should be indented 
with a
single tab. The line `DESTDIR=$(TARGET_DIR) install` appears to have two 
tabs.
Please use a single tab for the continuation. - [Source: Expert Intuition]

Best regards,
Gullient Dowan
Assisted by Buildroot Review Assistant (used 
nvidia/nemotron-3-ultra-550b-a55b:free).