LU-17398 build: quash rpmbuild false warning

LU-17398 build: quash rpmbuild false warning

Rewrite comment so %() is escaped and does not generate
a false and misleaning warning during build:

 sh: -c: line 0: syntax error near unexpected token `)'
 sh: -c: line 0: `)'
 warning: Macro expanded in comment on line 261: %()

Test-Parameters: trivial
Fixes: 67cd54d05d ("LU-16967 build: Separate lnet LND rpm packaging")
Signed-off-by: Shaun Tancheff <shaun.tancheff@hpe.com>
Change-Id: I94fa0da88a5c7f64461cd8fc3cea343a7a087413
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/53604
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>
Reviewed-by: James Simmons <jsimmons@infradead.org>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>