video: exynos_fb: Make a call to draw_logo only when CONFIG_CMD_BMP is selected

Previously, the call to draw_logo() was happening irrespective
of whether we have selected logo or LCD console.
With this patch we call draw_logo() only when CONFIG_CMD_BMP is selected.

This would even fix the following compilation warning:
exynos_fb.c: In function 'draw_logo':
exynos_fb.c:74:8: warning: variable 'addr' set but not used
[-Wunused-but-set-variable]
exynos_fb.c:73:9: warning: variable 'y' set but not used
[-Wunused-but-set-variable]
exynos_fb.c:73:6: warning: variable 'x' set but not used
[-Wunused-but-set-variable]

Signed-off-by: Ajay Kumar <ajaykumar.rs@samsung.com>
Signed-off-by: Minkyu Kang <mk7.kang@samsung.com>