CONFIG_MACH_PCM990_BASEBOARD is not available for thedefaultarchitecture x86.
Result is shown for architecture arm

PHYTEC PCM-990 development board

modulename: pcm990-baseboard.ko

configname: CONFIG_MACH_PCM990_BASEBOARD

Used baseboard
└─>PHYTEC PCM-990 development board
In linux kernel since version 2.6.25 (release Date: 2008-04-16)  
source code:
arch/arm/mach-pxa/pcm990-baseboard.c
selects

CONFIG_HAVE_PWM

depends
 or CONFIG_ARCH_PXA |
| CONFIG_MACH_PCM027 or  NOT CONFIG_ARCH_PXA_V7